U.S. patent application number 16/326918 was filed with the patent office on 2019-07-11 for absorbent article and method for manufacturing pull-on absorbent article.
This patent application is currently assigned to UNICHARM CORPORATION. The applicant listed for this patent is UNICHARM CORPORATION. Invention is credited to Jun FUKASAWA, Kunihiko KATSURAGAWA, Toshiyasu YOSHIOKA.
Application Number | 20190209397 16/326918 |
Document ID | / |
Family ID | 61301505 |
Filed Date | 2019-07-11 |
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United States Patent
Application |
20190209397 |
Kind Code |
A1 |
FUKASAWA; Jun ; et
al. |
July 11, 2019 |
ABSORBENT ARTICLE AND METHOD FOR MANUFACTURING PULL-ON ABSORBENT
ARTICLE
Abstract
An absorbent article including an absorbent main body including
an absorbent body. The absorbent main body having a longitudinal
direction conforming to a vertical direction; and
waist-circumference sections in a pair respectively located on one
end side and another end side in the longitudinal direction of the
absorbent main body. The waist-circumference sections each
including an elastic memberstretchable in a lateral direction. The
absorbent main body including a pair of extension sections
respectively extending outward on two sides of the absorbent body.
The extension sections each having an elastic member stretchable in
the vertical direction. The extension sections are formed extending
laterally outward from a position on a non-skin side of the
absorbent body using a continuous sheet that is continuous in the
lateral direction. A welded region having a predetermined length in
the lateral direction is in a portion where each of the extension
sections forms a leg opening.
Inventors: |
FUKASAWA; Jun; (Kagawa,
JP) ; YOSHIOKA; Toshiyasu; (Kagawa, JP) ;
KATSURAGAWA; Kunihiko; (Kagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
UNICHARM CORPORATION |
Shikokuchuo-City, Ehime |
|
JP |
|
|
Assignee: |
UNICHARM CORPORATION
Shikokuchuo-City, Ehime
JP
|
Family ID: |
61301505 |
Appl. No.: |
16/326918 |
Filed: |
July 5, 2017 |
PCT Filed: |
July 5, 2017 |
PCT NO: |
PCT/JP2017/024696 |
371 Date: |
February 21, 2019 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61F 13/15739 20130101;
A61F 13/496 20130101; A61F 13/49413 20130101; A61F 2013/49093
20130101; A61F 13/49019 20130101; A61F 13/494 20130101; A61F
13/15804 20130101; A61F 13/4963 20130101; A61F 13/15585 20130101;
A61F 13/49061 20130101 |
International
Class: |
A61F 13/49 20060101
A61F013/49; A61F 13/494 20060101 A61F013/494; A61F 13/15 20060101
A61F013/15; A61F 13/496 20060101 A61F013/496 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 29, 2016 |
JP |
2016-167106 |
Aug 29, 2016 |
JP |
2016-167107 |
Claims
1. An absorbent article having a vertical direction and a lateral
direction, the absorbent article comprising: an absorbent main body
including an absorbent body, the absorbent main body having a
longitudinal direction that conforms to the vertical direction; and
waist-circumference sections in a pair respectively located on one
end side and another end side in the longitudinal direction of the
absorbent main body, the waist-circumference sections including an
elastic member stretchable in the lateral direction, the absorbent
main body including extension sections in a pair respectively
extending outward on two lateral sides of the absorbent body, the
extension sections each having an elastic member stretchable in the
vertical direction placed therein, the extension sections being
formed extending laterally outward from a position on a non-skin
side of the absorbent body using a continuous sheet that is
continuous in the lateral direction, a welded region having a
predetermined length in the lateral direction being placed in a
portion where each of the extension sections forms a leg
opening.
2. The absorbent article according to claim 1, wherein the welded
region includes a first welded region and a second welded region,
and in the portion where each of the extension sections forms the
leg opening, a portion of the continuous sheet where the first
welded region is placed and a portion of the continuous sheet where
the second welded region is placed are superimposed on each other
by being folded in a thickness direction of the extension
sections.
3. The absorbent article according to claim 2, wherein at least a
portion of the first welded regions and at least a portion of the
second welded regions are not superimposed on each other in plan
view in the thickness direction.
4. The absorbent article according to any one of claim 1, wherein
the welded region is placed inside of an outer end in the lateral
direction of each of the extension sections.
5. The absorbent article according to claim 1, wherein the
continuous sheet is folded on itself in the portion where each of
the extension sections forms the leg opening, a liquid impermeable
sheet is placed between the absorbent body and the continuous sheet
and between portions of the folded continuous sheet, and the liquid
impermeable sheet is placed inside of the outer end in the lateral
direction of each of the extension sections.
6. The absorbent article according to claim 1, wherein the elastic
member that is stretchable in the vertical direction and placed in
each of the extension sections intersects with the welded
region.
7. The absorbent article according to claim 1, wherein the elastic
member that is stretchable in the vertical direction and placed in
each of the extension sections is placed at a position between the
absorbent body and the welded region in the lateral direction.
8. The absorbent article according to claim 1, wherein the elastic
member that is stretchable in the vertical direction and placed in
the extension section is placed at a position of the outer end in
the lateral direction of each of the extension sections.
9. The absorbent article according to claim 1, wherein the
absorbent main body includes leak prevention wall sections in a
pair in two lateral side portions of the absorbent body,
respectively, the leak prevention wall sections being raisable
toward a wearer, and the leak prevention wall sections are formed
using the continuous sheet.
10. The absorbent article according to claim 1, wherein the
extension sections in a pair are formed using the continuous sheet
that is shared between the extension sections.
11. A method for manufacturing a pull-on absorbent article having a
vertical direction, a lateral direction, and a thickness direction,
the pull-on absorbent article including an absorbent body and an
exterior sheet, the absorbent body having a longitudinal direction
conforming to the vertical direction, the exterior sheet being
superimposed on the absorbent body on a non-skin side, the exterior
sheet extending laterally outward from a position on a non-skin
side of the absorbent body, the exterior sheet being continuous in
the lateral direction, the method comprising: a welded region
forming step of forming a welded region having a predetermined
length in the lateral direction by welding a portion where the
exterior sheet is superimposed on itself in the thickness
direction; an elastic member placing step of placing an elastic
member in a predetermined region of the exterior sheet, the elastic
member being stretchable in the vertical direction; and a
leg-circumference extension section forming step of forming
leg-circumference extension sections each in which at least a
portion of the elastic member overlaps in the lateral direction
with the welded region, the leg-circumference extension sections
respectively extending on two lateral sides of the absorbent
body.
12. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein in the welded region forming step,
two end portions in the lateral direction of the exterior sheet in
an unfolded state are folded back on themselves in the lateral
direction from outside to inside, and the welded region is formed
in a folded portion obtained by folding the exterior sheet in the
thickness direction, and in the leg-circumference extension section
forming step, the leg-circumference extension section is formed by
folding two end portions of the exterior sheet in the lateral
direction on themselves once again from outside to inside.
13. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein in the elastic member placing step,
the elastic member is placed so as to overlap with at least a
portion of the welded regions in the lateral direction.
14. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein the welded region includes a first
welded region and a second welded region, and the first welded
region and the second welded region are discontinuous in the
lateral direction.
15. The method for manufacturing a pull-on absorbent article
according to claim 14, wherein in the leg-circumference extension
section forming step, the exterior sheet is folded back on itself
at a predetermined position between the first welded region and the
second welded region in the lateral direction.
16. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein the welded region is formed to be
inclined at a predetermined angle with respect to the lateral
direction.
17. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein the welded region is formed such
that a plurality of dots are arranged in the lateral direction.
18. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein leak prevention wall sections in a
pair configured to be raised toward a wearer's skin side are
respectively formed in two lateral side portions of the absorbent
body, and the welded region is formed at a position not overlapping
in the lateral direction with a position corresponding to a base
for raising each of the leak prevention wall sections.
19. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein a plurality of the elastic members
are placed side by side in the lateral direction in each of the
leg-circumference extension sections, and the elastic member
provided on an innermost side in the lateral direction among the
plurality of elastic members is placed between the absorbent body
and the welded region in the lateral direction.
20. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein the plurality of elastic members are
provided side by side in the lateral direction in each of the
leg-circumference extension sections, and the elastic member
provided on an outermost side in the lateral direction among the
plurality of elastic members is provided at an outer end in the
lateral direction of each of the leg-circumference extension
sections.
21. The method for manufacturing a pull-on absorbent article
according to claim 11, wherein a liquid impermeable back sheet is
provided on a skin side of the elastic member that is placed so as
to overlap with the welded region in the lateral direction.
Description
TECHNICAL FIELD
[0001] The present disclosure relates to an absorbent article and a
method for manufacturing a pull-on absorbent article.
BACKGROUND ART
[0002] An absorbent article includes a disposable diaper as an
example thereof. A disposable diaper including an absorbent main
body and a waist belt is disclosed in Patent Literature 1. The
waist belt of this diaper includes an inner sheet portion, an outer
sheet portion, and a cushion forming sheet portion placed between
these sheet portions. A waist stretchable member is also fixed in a
stretched state between the outer sheet portion and the cushion
forming sheet portion. The cushion forming sheet portion and the
inner sheet portion are joined together in a discontinuous manner
along the waist circumference. Accordingly, gaps are formed in
non-joined portions where the cushion forming sheet portion and the
inner sheet portion are not joined together, thereby being able to
reduce irritation caused to a wearer's skin.
CITATION LIST
Patent Literature
[0003] [PTL 1] Japanese Patent Application Publication No.
2013-70711
SUMMARY OF INVENTION
Technical Problem
[0004] In order to prevent lateral leakage of excrement, the above
diaper is configured such that second barrier cuffs (extension
sections) provided so as to extend outward on both lateral sides of
an absorbent body, thereby closely fitting the second barrier cuffs
around the wearer's legs. Each of the second barrier cuffs includes
three stretchable members placed in rows along the lateral
direction, and has a width in the lateral direction. The second
barrier cuffs are, however, easily affected by the waist
stretchable members, and thus might contract in the lateral
direction or curl. In such a case, the second barrier cuffs are not
be able to closely fit around the wearer's legs through face
contact, thereby reducing effectiveness in prevention of lateral
leakage. Further, the second barrier cuffs are formed by joining a
side sheet and a cover sheet together. Accordingly, excrement is
likely to seep out from a seam between the two sheets.
[0005] The present disclosure achieved in consideration of such
issues as describe above, an object of the present disclosure is to
provide an absorbent article that is suppressed from leaking from
around the legs.
Solution to Problem
[0006] A primary aspect of the present disclosure is an absorbent
article having a vertical direction and a lateral direction, the
absorbent article comprising: an absorbent main body including an
absorbent body, the absorbent main body having a longitudinal
direction that conforms to the vertical direction; and
waist-circumference sections in a pair respectively located on one
end side and another end side in the longitudinal direction of the
absorbent main body, the waist-circumference sections including an
elastic member stretchable in the lateral direction, the absorbent
main body including extension sections in a pair respectively
extending outward on two lateral sides of the absorbent body, the
extension sections each having an elastic member stretchable in the
vertical direction placed therein, the extension sections being
formed extending laterally outward from a position on a non-skin
side of the absorbent body using a continuous sheet that is
continuous in the lateral direction, a welded region having a
predetermined length in the lateral direction being placed in a
portion where each of the extension sections forms a leg
opening.
[0007] At least following matters will become clear from the
descriptions of the present specification with reference to the
accompanying drawings.
Advantageous Effects of Invention
[0008] According to the present disclosure, it is possible to
provide a pull-on absorbent article that is suppressed from leaking
from around legs.
BRIEF DESCRIPTION OF DRAWINGS
[0009] FIG. 1 is a schematic perspective view of a pull-on
disposable diaper 1.
[0010] FIG. 2 is a schematic plan view of the diaper 1 in an
unfolded and extended state when viewed from a skin-side.
[0011] FIG. 3 is a schematic cross-section of the diaper 1.
[0012] FIG. 4A and FIG. 4B are diagrams to explain a method of
forming an absorbent main body 10.
[0013] FIG. 5 is an explanatory diagram of the absorbent main body
10 and adhesive regions 40 of a pair of waist-circumference
sections 20, 30.
[0014] FIG. 6 is a diagram to explain characteristics of
leg-circumference extension sections 60.
[0015] FIG. 7 is an enlarged diagram illustrating lateral welded
regions 62 and vertical welded regions 66.
[0016] FIG. 8 is a diagram illustrating a state in which the
leg-circumference extension sections 60 closely fit the wearer.
[0017] FIG. 9A to FIG. 9C are diagrams to explain modified examples
of the lateral welded regions 62.
[0018] FIG. 10 is a diagram to illustrate a flow of manufacturing
the absorbent main body 10.
[0019] FIG. 11 is a plan view and a cross-section to explain an LSG
elastic member placing process.
[0020] FIG. 12 is a plan view and a cross-section to explain a
welded region forming process.
[0021] FIG. 13 is an enlarged diagram illustrating a region A in
FIG. 12.
[0022] FIG. 14 is a plan view and a cross-section to explain an
elastic member placing process.
[0023] FIG. 15 is a plan view and a cross-section to explain an
absorbent body transferring process.
[0024] FIG. 16 is a plan view and a cross-section to explain a
leg-circumference extension section forming process.
DESCRIPTION OF EMBODIMENTS
[0025] At least following matters will become clear from the
descriptions of the present specification with reference to the
accompanying drawings.
[0026] An absorbent article having a vertical direction and a
lateral direction, the absorbent article comprising: an absorbent
main body including an absorbent body, the absorbent main body
having a longitudinal direction that conforms to the vertical
direction; and waist-circumference sections in a pair respectively
located on one end side and another end side in the longitudinal
direction of the absorbent main body, the waist-circumference
sections including an elastic member stretchable in the lateral
direction, the absorbent main body including extension sections in
a pair respectively extending outward on two lateral sides of the
absorbent body, the extension sections each having an elastic
member stretchable in the vertical direction placed therein, the
extension sections being formed extending laterally outward from a
position on a non-skin side of the absorbent body using a
continuous sheet that is continuous in the lateral direction, a
welded region having a predetermined length in the lateral
direction being placed in a portion where each of the extension
sections forms a leg opening.
[0027] According to such an absorbent article, the extension
sections have higher stiffness in the lateral direction at the
portions where the extension sections form the leg openings, and
such portions are likely to be maintained with some widths in the
lateral direction, thereby being able to closely fit around the
legs of the wearer through face contact. Accordingly, leakage from
around the legs is suppressed. Further, there is no seam in a sheet
exposed to the non-skin side faces of the extension sections and
the vicinity thereof, thereby suppressing seeping out of excrement
from seams between sheets.
[0028] In such an absorbent article, the welded region includes a
first welded region and a second welded region, and in the portion
where each of the extension sections forms the leg opening, a
portion of the continuous sheet where the first welded region is
placed and a portion of the continuous sheet where the second
welded region is placed are superimposed on each other by being
folded in a thickness direction of the extension sections.
[0029] According to such an absorbent article, the stiffness in the
lateral direction is further increased in the portions where the
extension sections form the leg openings, and thus such portions
are likely to be maintained with some widths in the lateral
direction, thereby reliably suppressing leakage from around the
legs.
[0030] In such an absorbent article, at least a portion of the
first welded regions and at least a portion of the second welded
regions are not superimposed on each other in plan view in the
thickness direction.
[0031] According to such an absorbent article, the welded regions
are present in a wider flat surface range in the portions where the
extension sections form the leg openings, so that the stiffness in
the lateral direction is further increased, thereby more reliably
suppressing leakage from around the legs.
[0032] In such an absorbent article, the welded region is placed
inside of an outer end in the lateral direction of each of the
extension sections.
[0033] According to such an absorbent article, laterally outer end
portions of the portions where the extension sections form the leg
openings are soft, and are accordingly comfortable to the skin.
Further, the sandwiching force of the wearer's legs is absorbed,
and thus such portions are likely to be maintained with some widths
in the lateral direction, thereby suppressing leakage from around
the legs.
[0034] In such an absorbent article, the continuous sheet is folded
on itself in the portion where each of the extension sections forms
the leg opening, a liquid impermeable sheet is placed between the
absorbent body and the continuous sheet and between portions of the
folded continuous sheet, and the liquid impermeable sheet is placed
inside of the outer end in the lateral direction of each of the
extension sections.
[0035] According to such an absorbent article, laterally outer end
portions of the portions where the extension sections form the leg
openings are soft, and are accordingly comfortable to the skin.
Further, the sandwiching force of the wearer's legs is absorbed,
and thus such portions are likely to be maintained with some widths
in the lateral direction, thereby suppressing leakage from around
the legs.
[0036] In such an absorbent article, the elastic member that is
stretchable in the vertical direction and placed in each of the
extension sections intersects with the welded region.
[0037] According to such an absorbent article, in the portions
where the extension sections form the leg openings, the portions
where the welded regions are placed are integrally raised toward
the wearer's side by virtue of the contraction of the elastic
members, thereby closely fitting around the legs of the wearer
through face contact.
[0038] In such an absorbent article, the elastic member that is
stretchable in the vertical direction and placed in each of the
extension sections is placed at a position between the absorbent
body and the welded region in the lateral direction.
[0039] According to such an absorbent article, the portions where
the extension sections form the leg openings are raised toward the
wearer's side by virtue of the contraction of the elastic members,
so that an upright height is ensured, thereby being able to closely
fit around the legs of the wearer.
[0040] In such an absorbent article, the elastic member that is
stretchable in the vertical direction and placed in the extension
section is placed at a position of the outer end in the lateral
direction of each of the extension sections.
[0041] According to such an absorbent article, the positions where
the extension sections form the leg openings are able to closely
fit the wearer up to the positions corresponding to the outer ends
in the lateral direction.
[0042] In such an absorbent article, the absorbent main body
includes leak prevention wall sections in a pair in two lateral
side portions of the absorbent body, respectively, the leak
prevention wall sections being raisable toward a wearer, and the
leak prevention wall sections are formed using the continuous
sheet.
[0043] According to such an absorbent article, there are no seam in
sheet at the boundary between the extension section and the leak
prevention wall section, thereby further suppressing leakage from
around the legs.
[0044] In such an absorbent article, the extension sections in a
pair are formed using the continuous sheet that is shared between
the extension sections.
[0045] According to such an absorbent article, there is no seam in
a sheet exposed to the non-skin side face of the absorbent main
body, thereby suppressing leakage from a seam between sheets.
Further, the pair of extension sections are integrally raised
together when the diaper is worn, and thus the pair of extension
sections can closely fit around the legs of the wearer in a
balanced manner.
[0046] Further, a method for manufacturing a pull-on absorbent
article having a vertical direction, a lateral direction, and a
thickness direction, the pull-on absorbent article including an
absorbent body and an exterior sheet, the absorbent body having a
longitudinal direction conforming to the vertical direction, the
exterior sheet being superimposed on the absorbent body on a
non-skin side, the exterior sheet extending laterally outward from
a position on a non-skin side of the absorbent body, the exterior
sheet being continuous in the lateral direction, the method
comprising: a welded region forming step of forming a welded region
having a predetermined length in the lateral direction by welding a
portion where the exterior sheet is superimposed on itself in the
thickness direction; an elastic member placing step of placing an
elastic member in a predetermined region of the exterior sheet, the
elastic member being stretchable in the vertical direction; and a
leg-circumference extension section forming step of forming
leg-circumference extension sections each in which at least a
portion of the elastic member overlaps in the lateral direction
with the welded region, the leg-circumference extension sections
respectively extending on two lateral sides of the absorbent
body.
[0047] According to such a method for manufacturing a pull-on
absorbent article, the leg-circumference extension sections are
suppressed from contracting and curling in the lateral direction,
by virtue of the provision of the welded regions. This makes it
possible to provide a pull-on absorbent article in which the
leg-circumference extension sections are likely to be maintained in
a planar shape with some widths in the lateral direction. Moreover,
a contraction force in the vertical direction caused by the
leg-circumference elastic members acts, thereby forming many
creases along the lateral direction on the surface of the
leg-circumference extension sections. With the undulations of such
creases, it is possible to provide a pull-on absorbent article
having pleasant feel to the touch.
[0048] In such a method for manufacturing a pull-on absorbent
article, it is preferable that, in the welded region forming step,
two end portions in the lateral direction of the exterior sheet in
an unfolded state are folded back on themselves in the lateral
direction from outside to inside, and the welded region is formed
in a folded portion obtained by folding the exterior sheet in the
thickness direction, and in the leg-circumference extension section
forming step, the leg-circumference extension section is formed by
folding two end portions of the exterior sheet in the lateral
direction on themselves once again from outside to inside.
[0049] According to such an absorbent article, the extension
sections are integrally formed by folding a single exterior sheet
back on itself, and thus there is no seam in a sheet member formed
in the extension sections. This makes it possible to suppress
leakage of excrement from a seam between sheets in the vicinity
around the legs of the wearer.
[0050] In such a method for manufacturing a pull-on absorbent
article, it is preferable that, in the elastic member placing step,
the elastic member is placed so as to overlap with at least a
portion of the welded regions in the lateral direction.
[0051] According to such a method for manufacturing a pull-on
absorbent article, welding can be performed without cutting
leg-circumference elastic members. That is, in the
leg-circumference extension sections, the welded regions can be
formed in regions overlapping the leg-circumference elastic members
without damaging the stretching force of the leg-circumference
elastic members. Accordingly it is possible to easily manufacture a
pull-on absorbent article having leg-circumference extension
sections that are likely to be maintained in a planar shape and
less likely to be curled when worn.
[0052] In such a method for manufacturing a pull-on absorbent
article, it is preferable that the welded region includes a first
welded region and a second welded region, and the first welded
region and the second welded region are discontinuous in the
lateral direction.
[0053] According to such a method for manufacturing a pull-on
absorbent article, it is possible to provide portions having high
stiffness and portions having low stiffness, in the portions where
the welded regions are formed and the portions where the welded
regions are not formed, in the lateral direction in the exterior
sheet.
[0054] In such a method for manufacturing a pull-on absorbent
article, it is preferable that, in the leg-circumference extension
section forming step, the exterior sheet is folded back on itself
at a predetermined position between the first welded region and the
second welded region in the lateral direction.
[0055] According to such a method for manufacturing a pull-on
absorbent article, the stiffness of the exterior sheet does not
become too high at predetermined positions, thereby being able to
tightly folding back the exterior sheet at these predetermined
positions. Accordingly, the leg-circumference extension sections
are likely to be formed into neat planar shapes.
[0056] In such a method for manufacturing a pull-on absorbent
article, it is preferable that the welded region is formed to be
inclined at a predetermined angle with respect to the lateral
direction.
[0057] According to such a method for manufacturing a pull-on
absorbent article, the welded regions are formed while the point to
which pressure is applied is being sequentially shifted along with
the rotation of the embossing roller that is configured to form the
welded region, so that local welding defects or the like are less
likely to occur and stable welding is achieved. Moreover, since the
place where pressure is applied is sequentially shifted, the
projections (e.g., ultrasound horns) provided on the outer
circumferential face of the embossing roller are less likely to be
worn out, thereby being able to efficiently manufacture a pull-on
absorbent article.
[0058] In such a method for manufacturing a pull-on absorbent
article, it is preferable that the welded region is formed such
that a plurality of dots are arranged in the lateral direction.
[0059] According to such a method for manufacturing a pull-on
absorbent article, partial welding is performed by using the
dot-shaped weld portions, so that the shape of each of the weld
portions (dots) becomes small, thereby easily concentrating and
repeatedly applying ultrasonic vibrations or the like onto
individual points. This makes it possible to stably perform welding
over the entire welded region.
[0060] In such a method for manufacturing a pull-on absorbent
article, it is preferable that leak prevention wall sections in a
pair configured to be raised toward a wearer's skin side are
respectively formed in two lateral side portions of the absorbent
body, and the welded region is formed at a position not overlapping
in the lateral direction with a position corresponding to a base
for raising each of the leak prevention wall sections.
[0061] According to such a method for manufacturing a pull-on
absorbent article, the portion (the side joined portions 53)
serving as the base for raising each of the leak prevention wall
sections does not overlap with the welded region, thereby
suppressing increase in the stiffness of the exterior sheet at this
base. Accordingly, the exterior sheet is likely to be folded
naturally based on the positions of the side joined portions,
thereby being able to raise the leak prevention wall sections
easily.
[0062] In such a method for manufacturing a pull-on absorbent
article, it is preferable that a plurality of the elastic members
are provided side by side in the lateral direction in each of the
leg-circumference extension sections, and the elastic member
provided on an innermost side in the lateral direction among the
plurality of elastic members is placed between the absorbent body
and the welded region in the lateral direction.
[0063] According to such a method for manufacturing a pull-on
absorbent article, the portions outside in the lateral direction of
the elastic members (61a) in the leg-circumference extension
sections serve as the bases for being raised toward the wearer's
skin side when the pull-on absorbent article is worn, by virtue of
the contraction of the elastic member (61a) provided innermost in
the lateral direction, and the upright height of the
leg-circumference extension sections is ensured. Accordingly, the
leg-circumference extension sections are likely to closely fit
around the legs of the wearer.
[0064] In such a method for manufacturing a pull-on absorbent
article, it is preferable that the plurality of elastic members are
provided side by side in the lateral direction in each of the
leg-circumference extension sections, and the elastic member
provided on an outermost side in the lateral direction among the
plurality of elastic members is placed at an outer end in the
lateral direction of each of the leg-circumference extension
sections.
[0065] According to such a method for manufacturing a pull-on
absorbent article, the leg-circumference extension sections are
likely to closely fit around the legs of the wearer by virtue of
the contraction force of the elastic members (61d) provided on the
outermost side in the lateral direction. Accordingly, the
degradation in fit of the leg-circumference extension sections are
likely to be suppressed, even in a case where the leg-circumference
extension sections are less likely to be maintained in a flat plane
shape in the laterally outer end portions.
[0066] In such a method for manufacturing a pull-on absorbent
article, a liquid impermeable back sheet is provided on a skin side
of the elastic member that is placed so as to overlap with the
welded region in the lateral direction.
[0067] According to such a method for manufacturing a pull-on
absorbent article, the back sheet is placed so as to cover the skin
side of the leg-circumference elastic members, thereby suppressing
the leg-circumference elastic members from being exposed to the
skin side, so that the adhesive applied to the surfaces of the
leg-circumference elastic members is suppressed from adhering to
the body of the wearer. Moreover, since the end joined portions and
the side joined portions are suppressed from contacting the
leg-circumference elastic members, a contraction force caused by
the leg-circumference elastic members is suppressed from acting on
the waist-circumference sections.
EMBODIMENTS
[0068] An absorbent article (a pull-on absorbent article) according
to the present disclosure will now be described using the following
embodiment in which a "pull-on disposable diaper" is employed as an
example thereof. The pull-on disposable diaper according to an
embodiment of the present disclosure may be used for infants or
adults.
Basic Configuration of Pull-On Disposable Diaper
[0069] FIG. 1 is a schematic perspective view of a pull-on
disposable diaper 1 (hereinafter referred to as a "diaper"). FIG. 2
is a schematic plan view of the diaper 1 in an unfolded and
stretched state, as viewed from a skin-side face. FIG. 3 is a
schematic cross-section of the diaper 1. FIG. 4A and FIG. 4B are
diagrams to explain a method of forming an absorbent main body 10.
FIG. 5 is an explanatory diagram of the absorbent main body 10 and
adhesive regions 40 of a pair of waist-circumference sections 20,
30. Note that except for FIG. 1, the drawings illustrate states in
which the diaper 1 provided with elastic members has been stretched
to such an extent that creases in the diaper 1 are not visible.
Specifically, the stretched state illustrated indicates a state of
being stretched such that the dimensions of members configuring the
diaper 1 (such as those of an exterior sheet 14 described later,
for example) match or are close to the dimensions of the individual
members of their own.
[0070] As illustrated in FIG. 1, a vertical direction, a lateral
direction, and a front-rear direction are defined in the pull-on
diaper 1. A waist opening BH and a pair of leg openings LH are
formed in the diaper 1. In the vertical direction, the side of the
waist opening BH is an upper side, and the side that will be
disposed at the crotch of a wearer is a lower side. In the
front-rear direction, the side that will be disposed on the
wearer's belly side is a front side, and the side that will be
disposed on the wearer's back side is a rear side. The diaper 1 has
a thickness direction as illustrated in FIG. 3. The side in the
thickness direction that will contact the wearer is a skin side,
and the opposite side thereto is the non-skin side.
[0071] The diaper 1 is what is referred to as a three-piece type of
diaper, and includes an absorbent main body 10 and a pair of
waist-circumference sections 20, 30. The absorbent main body 10 has
a substantially rectangular shape in plan view, with the
longitudinal direction thereof oriented along the vertical
direction. The waist-circumference sections 20, 30 have
substantially rectangular shapes in plan view, with the
longitudinal directions thereof oriented along the lateral
direction. The waist-circumference section that will cover a belly
region of the wearer out of the pair of waist-circumference
sections 20, 30 is also referred to as a front waist-circumference
section 20, and the waist-circumference section that will cover a
back region of the wearer is also referred to as a back
waist-circumference section 30.
[0072] As illustrated in the unfolded state in FIG. 2, a central
portion of the front waist-circumference section 20 in the lateral
direction is positioned on one longitudinal end side of the
absorbent main body 10, and a central portion of the back
waist-circumference section 30 in the lateral direction is
positioned on the other longitudinal end side of the absorbent main
body 10. The non-skin-side face of the absorbent main body 10 and
the skin-side faces of the pair of waist-circumference sections 20,
30 are then joined together with an adhesive or the like at the
adhesive regions 40 illustrated in FIG. 5. From the unfolded state
of FIG. 2, the absorbent main body 10 is folded in two by folding
the absorbent main body 10 at its substantially central portion in
the longitudinal direction such that the front waist-circumference
section 20 and the back waist-circumference section 30 are
superimposed on each other. Then, by joining two lateral side
portions 20a of the front waist-circumference section 20 to two
lateral side portions 30a of the back waist-circumference section
30, respectively, the diaper 1 is formed into a pull-on diaper.
[0073] The front waist-circumference section 20 and the back
waist-circumference section 30 each include two soft sheets (21 and
21, and 31 and 31) of a nonwoven fabric or the like, and a
plurality of elastic members 22, 32 such as laterally stretchable
elastic strings or the like. In the following description, the
elastic members 22, 32 are also referred to as waist-circumference
elastic members 22, 32. The plural waist-circumference elastic
members 22, 32 are arranged in rows and spaced apart from each
other in the vertical direction, and are fixed between the two
sheets (21 and 21 or 31 and 31) in a stretched state along the
lateral direction. The front waist-circumference section 20 and the
back waist-circumference section 30 are accordingly stretchable in
the lateral direction, so as to fit the waist of the wearer.
[0074] The absorbent main body 10 includes a top sheet 11, an
absorbent body 12, a back sheet 13, and the exterior sheet 14, in
this order in the thickness direction from the skin side, as
illustrated in FIG. 3. The top sheet 11 maybe any sheet as long as
it is a liquid permeable sheet, and examples thereof include a
hydrophilic air-through nonwoven fabric and a hydrophilic spunbond
nonwoven fabric. The back sheet 13 may be any sheet as long as it
is a liquid impermeable sheet, and examples thereof include a
polyethylene film, a polypropylene film, and the like. The top
sheet 11 and the back sheet 13 have sizes that cover the entire
absorbent body 12. In an embodiment of the present disclosure, the
side portions on the two lateral sides of the top sheet 11 are
folded to the non-skin side of the absorbent body 12. The exterior
sheet 14 may be a liquid permeable sheet or a liquid impermeable
sheet. However, in an embodiment of the present disclosure, since
the leak prevention wall sections 50 are formed using the exterior
sheet 14, examples of the exterior sheet 14 include a hydrophobic
SMS nonwoven fabric and the like.
[0075] The absorbent body 12 has a substantially rectangular shape
in plan view, and includes an absorbent core 121 for absorbing
liquid, and a core-wrapping sheet 122 covering outer peripheral
faces of the absorbent core 121. The absorbent core 121 is
configured by molding a liquid-absorbent material into a
predetermined shape and, in an embodiment of the present
disclosure, is molded into a substantially hour-glass shape having
a narrowed central portion in the longitudinal direction thereof.
Examples of the liquid-absorbent material include materials
obtained by containing a highly absorbent polymer (so-called a
SAP), etc., in liquid-absorbent fibers, such as pulp fibers.
Examples of the core-wrapping sheet 122 include a liquid permeable
sheet such as tissue paper, a nonwoven fabric, or the like. Note
that the core-wrapping sheet 122 need not be provided.
[0076] The absorbent main body 10 includes the pair of leak
prevention wall sections 50 and a pair of leg-circumference
extension sections 60 (a pair of extension sections). More details
are described later, however, in an embodiment of the present
disclosure, the pair of leak prevention wall sections 50 and the
pair of leg-circumference extension sections 60 are integrally
formed such that the two lateral side portions of the single
exterior sheet 14 are folded, as illustrated in FIG. 3 and FIG.
4.
[0077] The leak prevention wall sections 50 in a pair extend along
the longitudinal direction of the absorbent main body 10, and are
provided at the two lateral side portions of the absorbent body 12,
respectively. More specifically, the leak prevention wall sections
50 are provided so as to span from a position superimposed on the
absorbent body 12 to a position extended laterally outward
therefrom. The leak prevention wall sections 50 each includes: an
elastic member 51 (hereinafter, also referred to as the "LSG
elastic member 51") stretchable in the longitudinal direction (the
vertical direction of the diaper 1); and a pair of end joined
portions 52 and a side joined portion 53 where the exterior sheet
14 for forming the leak prevention wall sections 50 is joined to
the top sheet 11 and the back sheet 13. The pairs of end joined
portions 52 are respectively placed at the two longitudinal end
portions of the absorbent main body 10. The side joined portions 53
in a pair extend from one end to the other end in the longitudinal
direction of the absorbent main body 10, and are placed outside in
the lateral direction of the end joined portions 52. Thus, in each
of the leak prevention wall sections 50, a portion in the exterior
sheet 14 between the pair of end joined portions 52 is raisable
toward the wearer (the skin side in the thickness direction) based
on the side joined portion 53 by virtue of contraction of the
elastic members 51. Accordingly, excrement having laterally flown
out is blocked by the leak prevention wall sections 50. However,
the diaper 1 may also be configured without the leak prevention
wall sections 50.
[0078] The leg-circumference extension sections 60 in a pair
respectively are parts that extend outwards to the two lateral
sides of the absorbent body 12. More specifically, the
leg-circumference extension sections 60 are defined as parts from
the respective laterally outer ends of the absorbent body 12 to the
laterally outer ends of the absorbent main body 10. Moreover, as
illustrated in FIG. 5, the leg-circumference extension sections 60
each includes a "leg opening forming portion 60a" to form each of
the leg openings LH, and a pair of "overlap portions 60b" that
respectively overlap with the front waist-circumference section 20
and the back waist-circumference section 30 in the vertical
direction. In other words, the leg-circumference extension sections
60 each include a pair of "overlap portions 60b" respectively
superimposed on the front waist-circumference section 20 and the
back waist-circumference section 30 in the thickness direction.
Each of the leg-circumference extension sections 60 includes four
elastic members 61 (hereinafter also referred to as
leg-circumference elastic members 61) stretchable in longitudinal
direction (the vertical direction of the diaper 1) and placed at an
interval in the lateral direction. Accordingly, the leg opening
forming portions 60a of the leg-circumference extension sections 60
fit around the legs of the wearer.
[0079] A plurality of "lateral welded regions 62 (welded regions of
the present disclosure)" are placed in each of the
leg-circumference extension sections 60 such that each lateral
welded region extends along the lateral direction while being
inclined with respect to the lateral direction. The plurality of
lateral welded regions 62 include, as illustrated in FIG. 3, a
plurality of first lateral welded regions 63 positioned on the skin
side in the thickness direction, and a plurality of second lateral
welded regions 64 positioned on the non-skin side in the thickness
direction. The plurality of first lateral welded regions 63 and the
plurality of second lateral welded regions 64 are, as illustrated
in FIG. 5, placed at intervals in the longitudinal direction in a
row over the entire longitudinal region of each of the
leg-circumference extension sections 60.
[0080] "Vertical welded regions 66" extending along the vertical
direction (longitudinal direction) are respectively placed in the
leg-circumference extension sections 60 at positions laterally
inside of the lateral welded regions 62. The vertical welded
regions 66 are also placed over the entire longitudinal region of
each of the leg-circumference extension sections 60, and include
first vertical welded regions 67 positioned on the skin side in the
thickness direction, and second vertical welded regions 68
positioned on the non-skin side in the thickness direction.
[0081] Although an example has been given in which string shaped
elastic members such as elastic strings are employed as the elastic
members (22, 32, 51, 61) provided in the front waist-circumference
section 20, the back waist-circumference section 30, the leak
prevention wall sections 50, and the leg-circumference extension
sections 60, it is not limited thereto. For example, a single or a
plurality of sheet-shaped elastic members such as a stretchable
film, a stretchable nonwoven fabric, or the like may be placed
therein instead of elastic strings. Moreover, only the parts where
stretchability is exhibited in the elastic members (so-called
effective length parts) are illustrated in the drawings.
Accordingly, parts of the elastic members where stretchability is
not exhibited may exist on their longitudinally outer sides of the
illustrated elastic members. The placement and numbers of the
elastic members are not limited to those of the illustrated
configuration.
Method of Forming the Absorbent Main Body 10
[0082] A simple description will now be given of a method of
forming the pair of leak prevention wall sections 50 and the pair
of leg-circumference extension sections 60 using the single
exterior sheet 14, with reference to FIGS. 4. The detailed method
of manufacturing the absorbent main body 10 in the manufacturing
process of the diaper 1 will be explained later.
[0083] First, as illustrated on the left side of FIG. 4A and FIG.
4B, the elastic member 51 used for the leak prevention wall section
50 is fixed to each lateral side portion of the exterior sheet 14
in a stretched state along the longitudinal direction. Then, using
the lateral position at which the elastic member 51 for each leak
prevention wall section 50 is fixed as a fold position f1, the two
lateral side portions of the exterior sheet 14 are folded back
toward the skin side in the thickness direction (inwards in the
lateral direction).
[0084] Then, as illustrated on the right side of FIG. 4A and FIG.
4B, the lateral welded regions 62 and the vertical welded regions
66 are formed by partially welding together portions in the
exterior sheet 14 having been folded on itself to form a double
layer. Specifically, in each of the portions where the exterior
sheet 14 is a double layer, the plurality of first lateral welded
regions 63 are formed in a portion on the laterally outer side and
placed at intervals in the longitudinal direction, and the
plurality of second lateral welded regions 64 are formed in a
portion on the laterally inner side and placed at intervals in the
longitudinal direction. The first vertical welded region 67 is
formed laterally outside of the first lateral welded regions 63,
and the second vertical welded region 68 is formed laterally inside
of the second lateral welded regions 64. The welded regions 62, 66
maybe formed by a known welding method, and examples thereof
include heat sealing, ultrasonic welding, welding by laser
irradiation, and the like.
[0085] An adhesive is then applied to the skin-side face of the
double-layered exterior sheet 14 in a portion laterally outside of
the lateral welded regions 62, so as to form the end joined
portions 52 and the side joined portion 53 of the leak prevention
wall sections 50. Then, the four leg-circumference elastic members
61 are fixed to the skin-side face of the exterior sheet 14 at a
portion laterally inside of the side joined portion 53 in a
stretched state along the longitudinal direction. Thereafter, the
back sheet 13 and the absorbent body 12 wrapped in the top sheet 11
are superimposed on and joined to a central portion in the lateral
direction of the exterior sheet 14.
[0086] Finally, the side portions at the two lateral sides of the
exterior sheet 14 are respectively folded back on the skin side in
the thickness direction with respect to the top sheet 11 at
respective fold positions f2 between the first lateral welded
regions 63 and the second lateral welded regions 64, thereby
forming the absorbent main body 10 illustrated in FIG. 3. That is,
the side portions on the two lateral sides of the exterior sheet 14
each are folded to form a quadruple layer. This results in the
first lateral welded regions 63 and the second lateral welded
regions 64 being superimposed on each other in the thickness
direction and the first vertical welded regions 67 and the second
vertical welded regions 68 being superimposed on each other in the
thickness direction. In the following description, respective
portions of the exterior sheet 14 of a quadruple layer are also
referred to as a first sheet portion 14a, a second sheet portion
14b, a third sheet portion 14c, and a fourth sheet portion 14d, in
this order from the skin side in the thickness direction. Each leak
prevention wall section 50 is constituted by the first sheet
portion 14a and second sheet portion 14b, and each
leg-circumference extension section 60 is constituted by the first
sheet portion 14a to fourth sheet portion 14d.
Leg-Circumference Extension Section 60
[0087] FIG. 6 is a diagram for explaining characteristics of the
leg-circumference extension sections 60. FIG. 7 is an enlarged
diagram illustrating the lateral welded regions 62 and the vertical
welded regions 66. FIG. 8 is a diagram illustrating a state in
which the leg-circumference extension sections 60 closely fit a
wearer. Note that the leak prevention wall sections 50 and the like
are omitted in FIG. 8 for the sake of brevity.
[0088] In the diaper 1 according to an embodiment of the present
disclosure, the lateral width of the leg-circumference extension
sections 60 is set to be comparatively wide. For example, in an S
size infant diaper 1, when the lateral width of the absorbent main
body 10 is 200 mm, the lateral width of each of the
leg-circumference extension sections 60 is set at about 40 mm. This
makes it possible to closely fit the leg-circumference extension
sections 60 around the legs of the wearer through a face having a
wide width. Accordingly, excrement is not likely to leak from
around the legs. Moreover, since the leg-circumference extension
sections 60 are set at the wide lateral width, a plurality of
strings (four in this case) of the leg-circumference elastic
members 61 can be placed side by side at intervals in the lateral
direction. Accordingly, the stretching force of the
leg-circumference extension sections 60 that is necessary to stop
lateral leakage can be shared among the plurality of the
leg-circumference elastic members 61. That is, since the stretching
force for each string of the leg-circumference elastic members 61
can be made smaller, a burden on the skin caused by local close
contact with the leg-circumference elastic members 61 can be
prevented.
[0089] The waist-circumference elastic members 22, 32 that are
stretchable in the lateral direction are provided in the
waist-circumference sections 20, 30 so that the disposable diaper 1
fits around the waist of the wearer. Accordingly, the leg opening
forming portions 60a in the leg-circumference extension sections 60
might be affected by the waist-circumference elastic members 22,
32, and contract in the lateral direction or curl inward or
outward. For example, if the diapers 1 are individually packaged
with the leg opening forming portions 60a in a curled and folded
state in the process of manufacturing the diaper 1, traces of
folding would remain in the leg opening forming portions 60a,
resulting in the diapers 1 being worn with the leg opening forming
portions 60a in a folded state.
[0090] In particular, the leg-circumference extension sections 60
according to an embodiment of the present disclosure are formed of
the exterior sheet 14 of the absorbent main body 10, and include
the overlap portions 60b that overlap with the waist-circumference
sections 20, 30. As illustrated in FIG. 5, portions of the overlap
portions 60b are joined to the waist-circumference sections 20, 30
with the adhesive regions 40. Thus, the overlap portions 60b are
likely to be affected by lateral contraction of the
waist-circumference sections 20, 30, and accordingly the leg
opening forming portions 60a might curl or contract in the lateral
direction. This might make it impossible to closely fit the
leg-circumference extension sections 60 around the wearer's legs
through face contact even though the leg-circumference extension
sections 60 are set wide in width.
[0091] Further, assuming here that the exterior sheet 14 has about
the same lateral width as that of the absorbent body 12, and the
leg-circumference extension sections 60 are formed not using the
exterior sheet 14 but using side sheets that are members separate
from the exterior sheet 14 and that extend laterally outward from
the exterior sheet 14, seams between the exterior sheet 14 and the
side sheets would be exposed to the non-skin-side face in the
vicinity of the leg opening forming portions 60a. Further, assuming
that leg opening forming portions 60a are formed not by folding
back the two lateral side portions of the exterior sheet 14 to
overlap, but by attaching side sheets that are members separate
from the exterior sheet 14 onto the skin-side face of the exterior
sheet 14, seams between the exterior sheet 14 and the side sheets
would be exposed to the laterally outer ends of the leg opening
forming portions 60a. With such a configuration, excrement would
seep out from the seams between sheets.
[0092] In contrast thereto, in the disposable diaper 1 according to
an embodiment of the present disclosure, the leg-circumference
extension sections 60 are formed using the exterior sheet 14 that
is continuous in the lateral direction as well as extends outwards
in the lateral direction from a position on the non-skin side of
the absorbent body 12. Further, a plurality of the lateral welded
regions 62 having a predetermined lateral length (L1 in FIG. 6) are
placed in each of the leg opening forming portions 60a ("a portion
where each of the extension sections forms a leg portion"
corresponding to the present disclosure). Note that the position on
the non-skin side of the absorbent body 12 refers to the position
on the non-skin side in the thickness direction with respect to the
absorbent body 12 as well as the position overlapping with the
absorbent body 12 in the lateral direction.
[0093] Thus, in the diaper 1, the stiffness in the lateral
direction of the leg opening forming portions 60a is enhanced by
the lateral welded regions 62, and the leg opening forming portions
60a are less likely to be affected by contraction in the lateral
direction of the waist-circumference sections 20, 30 and the
overlap portions 60b. As a result, the leg opening forming portions
60a are suppressed from contracting or curling in the lateral
direction, so that the leg opening forming portions 60a are likely
to be maintained in a state of having some lateral width (a
wide-width state). This makes it possible to closely fit the leg
opening forming portions 60a around the legs of the wearer through
a face having a wide width, thereby suppressing leakage of
excrement from around the legs of the wearer.
[0094] Moreover, in the diaper in the natural state (FIG. 1), since
the leg opening forming portions 60a extend in the lateral
direction substantially horizontally, the leg opening forming
portions 60a closely fit around the legs of the wearer through face
contact simply with the wearer passing his/her legs through the leg
openings LH of the diaper 1. This makes such an action unnecessary
as pulling out leg opening forming portions 60a that have curled
inwards by using fingers, for example, thereby being able to easily
wear the diaper 1 appropriately. Further, the wide-width state of
the leg opening forming portions 60a is more likely to be
maintained even while the diaper 1 is worn, so that the leg opening
forming portions 60a closely fit around the legs of the wearer
through face contact even when the sandwiching force of the legs of
the wearer acts. Further, the wide width leg opening forming
sections 60a closely fit the wearer, thereby being able to cover
the buttocks of the wearer. Thus, there is no need to provide, for
example, a cover or the like to cover the buttocks in addition to
the waist-circumference sections 20, 30, enabling simple
configuration of the diaper 1.
[0095] Further, in the diaper 1, the stiffness of the leg opening
forming portions 60a is increased by placing the lateral welded
regions 62 in the leg opening forming portions 60a. This can
facilitate manufacturing of the diapers 1 more, as compared with a
case in which the stiffness of the leg opening forming portions 60a
is increased by respectively providing separate members onto the
leg opening forming portions 60a, for example.
[0096] Further, by forming the leg-circumference extension sections
60 using the exterior sheet 14, it is possible to prevent the seams
between sheets from being exposed to the non-skin-side surface in
the leg opening forming portions 60a and the vicinity thereof.
Further, in the diaper 1 according to an embodiment of the present
disclosure, the lateral welded regions 62 are placed in the leg
opening forming portions 60a and the side portions of the exterior
sheet 14 are folded over to overlap. Accordingly, seams between
sheets are not exposed to the laterally outer ends 60d of the leg
opening forming portions 60a. Thus, in the diaper 1 according to an
embodiment of the present disclosure, excrement is prevented from
seeping out from seams between sheets, thereby further suppressing
leakage from around the legs.
[0097] Note that the lateral welded regions 62 according to an
embodiment of the present disclosure are, as illustrated in FIG. 7,
formed such that dot-shaped weld portions 69 (for example, weld
portions that are each formed by a protrusion in a protrusion
pattern provided on the outer circumferential face of an embossing
roller) are formed by being arranged in the lateral direction.
Specifically, pairs of rows each having three dots of the weld
portions 69 that are arranged to be inclined with respect to the
lateral direction are arranged in rows in the vertical direction
without being aligned with one another in the lateral direction.
Similarly, the vertical welded regions 66 are also formed such that
pairs of rows each having multiple of the dot-shaped weld portions
69 along the vertical direction are arranged in the lateral
direction without being aligned with one another in the vertical
direction. As such the welded regions 62, 66 may be obtained by
being partially welded, and in this case also, the lateral
stiffness of the leg opening forming portions 60a is increased.
Note that it is not limited thereto and, for example, the planar
shape of a single protrusion provided on the outer circumferential
face of an embossing roller may be formed into the same shape as
the welded regions 62, 66, such that the entire welded regions 62,
66 are welded. However, by forming each shape of the weld portions
69 to be small as in an embodiment of the present disclosure, a
pressure applied when welding is likely to be constant, thereby
achieving stable welding.
[0098] The predetermined lateral length of the lateral welded
regions 62 maybe of any length as long as it is greater than 0 mm,
however, the welded regions 62 are preferably elongated to some
extent. For example, in cases in which the lateral width of the
leg-circumference extension sections 60 is 40 mm, the length in the
lateral direction of the lateral welded regions 62 is preferably in
a range of from 7.5 mm to 27.5 mm, and is more preferably about
17.5 mm.
[0099] Moreover, the predetermined length in the lateral direction
of the lateral welded regions 62 (for example, L1 in FIG. 6)
indicates a length in the lateral direction from one end to the
other end in the lateral direction of the lateral welded regions
62. Accordingly, the shape of the lateral welded regions 62 may be
a shape extending parallel to the lateral direction (not
illustrated), and may also be a shape inclined with respect to the
lateral direction as in an embodiment of the present disclosure.
However, for example, when the axial direction of an embossing
roller corresponds to the lateral direction of the lateral welded
regions 62 and the lateral welded regions 62 are parallel to the
lateral direction, the lateral welded regions 62 are formed all at
once. In contrast thereto, when the lateral welded regions 62 are
inclined with respect to the lateral direction, each of the lateral
welded regions 62 is formed by sequential application of pressure
with the rotation of the embossing roller, thereby achieving stable
welding.
[0100] Further, the shape of the lateral welded regions 62 is not
limited to line shapes in which the dot-shaped weld portions 69 are
arranged in the lateral direction as in an embodiment of the
present disclosure. The lateral welded regions 62 maybe formed, for
example, in a rectangular shape, trapezoidal shape, elliptical
shape, barrel shape, or the like that are elongated in the lateral
direction. Further, the lateral weld portions 62 are not limited to
the dot-shaped weld portions 69, and the lateral welded regions 62
may be formed such that weld portions 69 of another shape, such as
a square shape, a triangular shape, or the like are arranged in the
lateral direction. Furthermore, a plurality of the lateral welded
regions 62 may be arranged in the lateral direction in each of the
leg opening forming portions 60a. The number of the lateral welded
regions 62 in each of the leg opening forming portions 60a may be
any as long as it is one or more.
[0101] In the diaper 1 according to an embodiment of the present
disclosure, a plurality of the lateral welded regions 62 are also
placed in the overlap portions 60b of the leg-circumference
extension sections 60. Thus, the stiffness in the lateral direction
of the overlap portions 60b is high and the overlap portions 60b
are suppressed from contracting in the lateral direction. That is,
a contraction force in the lateral direction from the
waist-circumference sections 20, 30 is less likely to be
transferred to the leg opening forming portions 60a via the overlap
portions 60b. Accordingly, the leg opening forming portions 60a are
further likely to be maintained in the wide-width state and the leg
opening forming portions 60a can closely fit around the legs of the
wearer through face contact, so that leakage from around the legs
is suppressed more reliably.
[0102] As illustrated in FIG. 5, the plurality of lateral welded
regions 62 are placed at constant intervals in the longitudinal
direction across the entire longitudinal region of the
leg-circumference extension sections 60a, thereby facilitating an
adjustment to the intervals in forming the lateral welded regions
62. Accordingly, manufacture of the diaper 1 is facilitated.
[0103] However, an embodiment may be such that the lateral welded
regions 62 may not be placed in the overlap portions 60b. An
embodiment may also be such that the lateral welded regions 62 are
placed in only one of the pair of overlap portions 60b of each of
the leg-circumference extension sections 60, while no lateral
welded regions 62 is placed in the other one of the overlap
portions 60b. In such cases, since the number of the lateral welded
regions 62, which are comparatively hard, is reduced, the burden on
the skin can be reduced, which makes the diaper 1 more comfortable
to wear. Further, the leg-circumference extension sections 60 do
not need to have a pair of the overlap portions 60b. That is, an
embodiment may be such that each of the leg-circumference extension
sections 60 only overlaps with only one of the front
waist-circumference section 20 and the back waist-circumference
section 30, or the leg-circumference extension sections 60 overlaps
with neither thereof.
[0104] Further, in the diaper 1 according to an embodiment of the
present disclosure, the leak prevention wall sections 50 are also
formed using the exterior sheet 14. In such a case, there are no
seam in the sheet in each boundary between the leak prevention wall
section 50 and the leg-circumference extension section 60, thereby
being able to further suppress leakage from around the legs. For
example, it is possible to prevent excrement blocked by the leak
prevention wall sections 50 from seeping out from each boundary
between the leak prevention wall section 50 and the
leg-circumference extension section 60 to soil the legs of the
wearer.
[0105] The exterior sheet 14 also extends laterally outward from a
position on the non-skin-side surface side of the absorbent body
12. That is, the pair of leg-circumference extension sections 60 is
formed using the shared exterior sheet 14. Accordingly, there is no
seam in the exterior sheet 14 exposed to the non-skin-side surface
of the absorbent main body 10, thereby suppressing leakage from a
seam in the sheet. Further, the pair of leg-circumference extension
sections 60 is integrally raised together when the diaper 1 is
worn. Accordingly, the pair of leg-circumference extension sections
60 can closely fit around the legs of the wearer in a balanced
manner, thereby suppressing leakage from around the legs.
[0106] Further, in the diaper 1 according to an embodiment of the
present disclosure, the pair of leak prevention wall sections 50 is
also formed using the shared exterior sheet 14. As such, the number
of materials can also be reduced by forming the leg-circumference
extension section 60 and the leak prevention wall section 50 on one
side in the lateral direction using the single exterior sheet 14,
or by respectively forming the pair of leg-circumference extension
sections 60 and the pair of leak prevention wall sections 50 on two
lateral sides using the single exterior sheet 14 as described
above. Thus, a cost reduction can be achieved. However, it is not
limited thereto. For example, the leak prevention wall section 50
and the leg-circumference extension section 60 may be formed using
separate sheets, respectively, the leg-circumference extension
sections 60 in a pair each may be formed using separate exterior
sheets 14, or the leg-circumference extension section 60 may be
formed using the liquid impermeable back sheet 13.
[0107] Moreover, as illustrated in FIG. 3, at the leg opening
forming portions 60a and the overlap portions 60b in the
leg-circumference extension sections 60, portions on the exterior
sheet 14 where the first lateral welded regions 63 are placed
(i.e., the first sheet portion 14a and the second sheet portion
14b), and portions on the exterior sheet 14 where the second
lateral welded regions 64 are placed (i.e., the third sheet portion
14c and the fourth sheet portion 14d) are superimposed on each
other in the thickness direction of the leg-circumference extension
sections 60.
[0108] Accordingly, the lateral stiffness of the leg opening
forming portions 60a and the overlap portions 60b is further
increased. The exterior sheet 14 is folded into a quadruple layer
to superimpose the first lateral welded regions 63 and the second
lateral welded regions 64 on each other. As such, the lateral
stiffness of the leg opening forming portions 60a and the overlap
portions 60b is increased also with an increase in the number of
stacked layers of the exterior sheet 14. Accordingly, the overlap
portions 60b are further less likely to be affected by contraction
of the waist-circumference sections 20, 30, and the leg opening
forming portions 60a are more likely to be maintained in a
wide-width state. This can closely fit the leg opening forming
portions 60a around the legs of the wearer through face contact,
and suppress leakage from around the legs more reliably.
[0109] In other words, with the first lateral welded regions 63 and
the second lateral welded regions 64 being superimposed on each
other, the stiffness of the leg opening forming portions 60a and
the stiffness of the overlap portions 60b can be ensured even when
the stiffness is lowered by reducing the welding strength per
lateral welded region 62. Accordingly, the lateral welded regions
62 can be comparatively softened, which makes the diaper 1 more
comfortable to wear. Further, it is possible to prevent the lateral
welded regions 62 from becoming too thin or into holes, which
results from trying to increase the welding strength so as to
increase the stiffness of the lateral welded regions 62.
[0110] However, it is not limited thereto. The plurality of lateral
welded regions 62 may not be superimposed on each other in the
thickness direction in the leg opening forming portions 60a and the
overlap portions 60b. In such a case, it is sufficient that the
exterior sheet 14 is folded into a double layer and the double
layer is welded to form the lateral welded regions 62.
Alternatively, three of more of the lateral welded regions 62 may
be superimposed on each other in the thickness direction.
[0111] Further, as illustrated in FIG. 6, the lateral welded
regions are placed inside of laterally outer ends 60d of the
leg-circumference extension sections 60 in the leg opening forming
portions 60a. That is, the lateral welded regions 62 are absent in
end portions on the laterally outer side in the leg opening forming
portions 60a, so that these end portions are soft and accordingly
comfortable to the skin of the wearer's legs contacting the end
portions, which makes the diaper 1 more comfortable to wear.
Further, the sandwiching force of the wearer's legs is absorbed.
Thus, even while the diaper 1 is worn, the leg opening forming
portions 60a are likely to be maintained in the wide-width state,
which closely fits the leg opening forming portions 60a around the
legs of the wearer through face contact, thereby suppressing
leakage from around the legs.
[0112] Further, as illustrated in FIG. 3, in the absorbent main
body 10, the back sheet 13 is disposed between the absorbent body
12 wrapped in the top sheet 11 and the exterior sheet 14 as well as
between folded portions of the exterior sheet 14. As illustrated in
FIG. 2, laterally outer ends 13a of the back sheet 13 are also
disposed inside of the laterally outer ends 60d of the
leg-circumference extension sections 60, respectively. Accordingly,
the back sheet 13 is absent in the end portions on the laterally
outer side in the leg opening forming portions 60a, so that these
end portions are soft and thus comfortable to the skin of the
wearer's legs contacting the end portions, which makes the diaper 1
more comfortable to wear. Further, the sandwiching force of the
wearer's legs is absorbed, and thus the leg opening forming
portions 60a are maintained in the wide-width state.
[0113] As illustrated in FIG. 2 and FIG. 3, in each of the leg
opening forming portions 60a, four leg-circumference elastic
members 61a to 61d are placed side by side in the lateral
direction. Two leg-circumference elastic members 61b, 61c
positioned in the center thereof intersect with the lateral welded
regions 62 placed in the leg opening forming portions 60a. The
portions where the lateral welded regions 62 are placed in the leg
opening forming portions 60a have high stiffness, and thus are
likely to be maintained in a planar shape. The portions where the
lateral welded regions 62 are placed in the leg opening forming
portion 60a are integrally raised to the wearer's side by virtue of
contraction of the leg-circumference elastic members 61b, 61c.
Thus, as illustrated in FIG. 7, such portions where the lateral
welded regions 62 are placed in the leg opening forming portions
60a can closely fit around the legs of the wearer through face
contact, thereby suppressing leakage from around the legs.
[0114] The leg-circumference elastic member 61a that is positioned
on the innermost side in the lateral direction among the four
leg-circumference elastic members 61a to 61d is placed at a
position between the absorbent body 12 and the lateral welded
regions 62 in the lateral direction. Thus, as illustrated in FIG.
7, portions laterally outside of the leg-circumference elastic
members 61a are raised to the wearer's side by virtue of
contraction of the leg-circumference elastic members 61a, thereby
ensuring an upright height. This can make it possible to closely
fit the leg opening forming portions 60a around the legs of the
wearer.
[0115] The leg-circumference elastic member 61d that is positioned
on the outermost side in the lateral direction among the four
leg-circumference elastic members 61a to 61d is placed at the
position of the laterally outer end 60d of each of the leg opening
forming portions 60a. Accordingly, the leg opening forming portions
60a are capable of securely fitting the wearer up to the position
of the laterally outer ends 60d by virtue of contraction of the
leg-circumference elastic members 61d. In particular, even in a
case in which the lateral welded regions 62 do not reach the
laterally outer ends 60d in the leg opening forming portions 60a,
the leg opening forming portions 60a can closely fit the wearer up
to the position of the laterally outer ends 60d.
[0116] The overlap portions 60b in the leg-circumference extension
sections 60 each include a non-joined region 41 (the regions 41
surrounded by bold lines in FIG. 5) where the overlap portion 60b
and the waist-circumference section 20, 30 are not joined together
in a position corresponding to the lower end portion in the
vertical direction of the waist-circumference section 20, 30. A
lateral welded region 62a is placed in the non-joined region
41.
[0117] In the overlap portions 60b, the non-joined regions 41 are
less likely to be affected by lateral contraction of the
waist-circumference sections 20, 30 than the adhesive regions 40
where the overlap portions 60b are joined to the
waist-circumference sections 20, 30 (diagonally hatched regions in
FIG. 5). Accordingly, by providing the non-joined region 41 in each
boundary portion between the overlap portion 60b and the leg
opening forming portion 60a, the boundary portion is likely to be
maintained in the wide-width state. Moreover, by placing the
lateral welded regions 62a in the boundary portion (the non-joined
regions 41), the boundary portion is more likely to be maintained
in a wide-width state. As a result, the leg opening forming portion
60a is also likely to be maintained in the wide-width state. In
other words, the lateral contraction force from the
waist-circumference sections 20, 30 is blocked by the lateral
welded regions 62 in the non-joined regions 41, so that the lateral
contraction force is unlikely to be transferred to the leg opening
forming portions 60a. Consequently, the leg opening forming
portions 60a are likely to be maintained in the wide-width state.
Thus, the leg opening forming portions 60a can closely fit around
the legs of the wearer through face contact, thereby suppressing
leakage from around the legs.
[0118] In the diaper 1, in addition to the adhesive regions 40
described above, joined regions 42, 43, 44 as illustrated in FIG. 3
are also provided, where the adhesive is applied. Specifically, the
first sheet portion 14a and the second sheet portion 14b of the
exterior sheet 14 forming the leak prevention wall sections 50 are
joined in the joined regions 42. The non-skin-side face of the
absorbent body 12 wrapped in the top sheet 11, and the back sheet
13 are also joined in the joined region 43 (hereinafter also
referred to as the "absorbent body joined portion 43"). The back
sheet 13 and the exterior sheet 14 are also joined in the joined
region 44 (hereinafter, also referred to as the "back sheet joined
portion 44").
[0119] Whereas, in laterally outer portions 60c of the
leg-circumference extension sections 60 illustrated in FIG. 3 (more
specifically, at the portions 60c further laterally outside of the
side joined portions 53 in the leak prevention wall sections 50),
the first sheet portion 14a and the second sheet portion 14b of the
exterior sheet 14 are not joined together with adhesive over the
entire longitudinal region thereof. Similarly, the third sheet
portion 14c and the fourth sheet portion 14d of the exterior sheet
14 are not joined together with adhesive over the entire
longitudinal region thereof. That is, the first sheet portion 14a
and the second sheet portion 14b of the exterior sheet 14 are not
joined together at portions each between the first lateral welded
regions 63 arranged along the longitudinal direction (for example,
the portions 65 in FIG. 5), so that gaps are each created
therebetween, resulting in high cushioning properties being
provided. Similarly, the third sheet portion 14c and the fourth
sheet portion 14d of the exterior sheet 14 are not joined together
at portions each between the second lateral welded regions 64
arranged along the longitudinal direction, so that gaps are each
created therebetween, resulting in high cushioning properties being
provided. Accordingly, by enhancing cushioning properties of the
leg-circumference extension sections 60 as such, the diaper 1
becomes more comfortable to wear.
[0120] Further, in the diaper 1 according to an embodiment of the
present disclosure, since the first lateral welded regions 63 and
the second lateral welded regions 64 are superimposed on each other
in the thickness direction, the first sheet portion 14a and the
second sheet portion 14b having high cushioning properties are
further superimposed on the third sheet portion 14c and the fourth
sheet portion 14d having high cushioning properties. Accordingly,
the cushioning properties in the leg-circumference extension
sections 60 are further enhanced.
[0121] The first vertical welded regions 67 and the second vertical
welded regions 68 are also provided in the leg-circumference
extension sections 60 according to an embodiment of the present
disclosure. Thus, even though the first sheet portion 14a and the
second sheet portion 14b are not joined together between the first
lateral welded regions 63, the first sheet portion 14a and the
second sheet portion 14b are firmly and closely joined together by
the first vertical welded regions 67. Similarly, the third sheet
portion 14c and the fourth sheet portion 14d are also firmly and
closely joined together by the second vertical welded regions 68.
Thus, the first sheet portion 14a and the second sheet portion 14b
are not likely to separate from each other, and the third sheet
portion 14c and the fourth sheet portion 14d are not likely to
separate from each other, for example, even when the sheet portions
are sandwiched between the wearer's legs. Accordingly, the leg
opening forming portions 60a are maintained in the wide-width
state. However, the first vertical welded regions 67 and the second
vertical welded regions 68 may not be provided.
[0122] The lateral welded regions 62 according to an embodiment of
the present disclosure are inclined with respect to the lateral
direction. Accordingly, the vertical length of the non-joined
portions between the first sheet portion 14a and the second sheet
portion 14b when the lateral regions 62 are inclined is smaller
than the vertical length of the non-joined portions, for example,
when the lateral regions 62 are parallel to the lateral direction.
Also, the vertical length of the non-joined portions between the
third sheet portion 14c and the fourth sheet portion 14d when the
lateral regions 62 are inclined is also smaller than the vertical
length when the lateral regions 62 are parallel thereto. Thus, the
first sheet portion 14a and the second sheet portion 14b are not
likely to separate, and the third sheet portion 14c and the fourth
sheet portion 14d are not likely to separate, so that the leg
opening forming portions 60a are maintained in the wide-width
state.
[0123] In the overlap portions 60b in the laterally outer portions
60c of the leg-circumference extension sections 60, the second
sheet portion 14b of the exterior sheet 14 and the back sheet 13,
and the back sheet 13 and the third sheet portion 14c of the
exterior sheet 14, may not be joined together with adhesive. In
particular, since the back sheet 13 and the third sheet portion 14c
are not joined together, end portions that are not fixed in a
stretched state of the leg-circumference elastic members 61 are
able to contract. This can prevent the leg-circumference elastic
members 61 from being exposed from the two longitudinal end
portions of the leg-circumference extension sections 60. The third
sheet portion 14c and the fourth sheet portion 14d of the exterior
sheet 14 are joined to the waist-circumference sections 20, 30
through the adhesive regions 40 and the lateral welded regions 62.
However, the first sheet portion 14a and the second sheet portion
14b of the exterior sheet 14 are away from the waist-circumference
sections 20, 30, and thus are not likely to be affected by lateral
contraction of the waist-circumference sections 20, 30.
Accordingly, the leg opening forming portions 60a are likely to be
maintained in the wide-width state. Even without joining the
above-described portions together, the end portions on the two
longitudinal ends of the leg-circumference extension sections 60
can be suppressed from being opened since the lateral welded
regions 62 are placed in the overlap portions 60b.
[0124] In the leg opening forming portions 60a of the laterally
outer portions 60c in the leg-circumference extension sections 60,
the second sheet portion 14b of the exterior sheet 14 and the back
sheet 13, and the back sheet 13 and the third sheet portion 14c of
the exterior sheet 14 are preferably joined together with adhesive.
With such a configuration, the four layers 14a to 14d of the
exterior sheet 14 are prevented from separating from each other
when being sandwiched between the wearer's legs. Thus, the leg
opening forming portions 60a are maintained in the wide-width
state.
[0125] As illustrated in FIG. 6, the plurality of
waist-circumference elastic members 22, 32 are placed at intervals
in the vertical direction in the waist-circumference sections 20,
30, and the plurality of lateral welded regions 62 are arranged at
intervals in the vertical direction in the overlap portions 60b. A
vertical interval L3 between the plurality of waist-circumference
elastic members 22, 32 is smaller than a vertical interval L2
between the plurality of lateral welded regions 62 placed in the
overlap portions 60b (L2>L3).
[0126] Accordingly, the number of the waist-circumference elastic
members 22, 32 is not too small, which can ensure the fit of the
waist-circumference sections 20, 30 to the wearer. That is, it is
possible to ensure the fit of the waist-circumference sections 20,
30 to the wearer while suppressing lateral contraction of the
overlap portions 60b and leakage from around the legs by virtue of
the lateral welded regions 62. Moreover, the number of the lateral
welded regions 62 placed in the overlap portions 60b is not too
great, which can prevent increase in the burden on the skin caused
by the comparatively hard lateral welded regions 62. Further, the
overlap portions 60b can be prevented from being torn from the
lateral welded regions 60b due to the intervals between the lateral
welded regions 62 being too small.
[0127] However, the configuration is not limited to the above. The
vertical interval L2 of the lateral welded regions 62 placed in the
overlap portions 60b may be equal to or smaller than the vertical
interval L3 of the waist-circumference elastic members 22, 32. In
such a case, the number of the lateral welded regions 62 is
increased, so that lateral contraction of the overlap portions 60b
is suppressed more reliably. The above comparison may be made using
an interval between the waist-circumference elastic members 22, 32
located at the same vertical position as the position of the
overlap portions 60b, or using an interval between the
waist-circumference elastic members 22, 32 located above the
overlap portions 60b. In cases in which the intervals between the
lateral welded regions 62 and the intervals between the
waist-circumference elastic members 22, 32 are not constant, the
intervals therebetween maybe any intervals as long as at least one
of the intervals between the waist-circumference elastic members
22, 32 is smaller than at least one of the intervals between the
lateral welded regions 62.
[0128] The lateral welded regions 62 placed in the overlap portions
60b are preferably not superimposed on the waist-circumference
elastic members 22, 32 in plan view in the thickness direction of
the leg-circumference extension sections 60 (FIG. 6). That is, the
lateral welded regions 62 preferably deviate in the vertical
direction from the waist-circumference elastic members 22, 32. This
can prevent contraction in portions of the waist-circumference
elastic members 22, 32 that are overlapped with the overlap
portions 60b from being excessively suppressed by the lateral
welded regions 62, so that such portions of the waist-circumference
elastic members 22, 32 contract appropriately. Accordingly, it is
possible to effectively utilize the waist-circumference elastic
members 22, 32 and ensure the fit of the waist-circumference
sections 20, 30 to the wearer. However, it is not limited thereto.
The vertical positions of some or all of the plurality of lateral
welded regions 62 may coincide with vertical positions of the
waist-circumference elastic members 22, 32.
[0129] As illustrated in FIG. 6, waist-circumference elastic
members 22a, 32a located above the absorbent body 12 in the
vertical direction extend continuously from one side portion to the
other side portion in the lateral direction of the
waist-circumference section 20, 30. In contrast,
waist-circumference elastic members 22b, 32b located at the same
vertical position as the absorbent body 12 each include a portion
from one side portion in the lateral direction of the
waist-circumference section 20, 30 to one side portion in the
lateral direction of the absorbent body 12, and a portion from the
other side portion in the lateral direction of the absorbent body
12 to the other side portion in the lateral direction of the
waist-circumference section 20, 30. That is, the
waist-circumference elastic members 22b, 32b each include a
discontinuous portion in a position superimposed on the absorbent
body 12 in the thickness direction of the waist-circumference
section 20, 30 (for example, from point a to point b in FIG.
6).
[0130] Thus, the absorbent body 12 is not likely to be affected by
lateral contraction of the waist-circumference elastic members 22,
32, thereby being able to suppress the absorbent body 12 from be
twisted. This causes the absorbent body 12 to closely fit the
wearer such that excrement is properly absorbed by the absorbent
body 12, thereby suppressing leakage from around the legs. Since
the absorbent body 12 is suppressed from being twisted, the leg
opening forming portions 60a can be extended substantially
horizontally to the lateral direction. This can closely fit the leg
opening forming portions 60a around the legs of the wearer through
face contact, thereby suppressing leakage from around the legs.
Modified Examples
[0131] FIG. 9A to FIG. 9C are diagrams for explaining modified
examples of the lateral welded regions 62. Diagrams on the left
side of FIG. 9A to FIG. 9C illustrate a state in which the first
lateral welded regions 63 and the second lateral welded regions 64
have been formed in the exterior sheet 14 during manufacture of the
diaper 1. The diagrams on the right side illustrate positional
relationships between the first lateral welded regions and the
second lateral welded regions 64 in the leg-circumference extension
sections 60.
[0132] In an embodiment described above, the first lateral welded
regions 63 and the second lateral welded regions 64 are formed
symmetrically with respect to the fold position f2 of the exterior
sheet 14, as illustrated in FIG. 4, that is, their inclination
directions are symmetrical to each other and vertical positions
match each other. Accordingly, in each of the leg opening forming
portions 60a and the overlap portions 60b, the first lateral welded
regions 63 and the second lateral welded regions 64 are placed so
as to be superimposed on each other in the thickness direction.
However, it is not limited thereto. Some or all of the first
lateral welded regions 63 and the second lateral welded regions 64
may not be superimposed on each other in plan view in the thickness
direction. That is, in each of the leg opening forming portions 60a
and the overlap portions 60b, the positions in a flat plane (the
positions in the lateral direction and the vertical direction) of
the first lateral welded regions 63 may deviate from the positions
in a flat plane of the second lateral welded regions 64.
[0133] For example, as illustrated on the left side in FIG. 9A, the
first lateral welded regions 63 and the second lateral welded
regions 64 may be formed such that their inclination directions are
symmetrical with respect to the fold position f2 and their
positions deviate from each other in the vertical direction. In
such a case, as illustrated on the right side of FIG. 9A, the first
lateral welded regions 63 and the second lateral welded regions 64
that are inclined in the same direction as each other are arranged
alternately in the vertical direction in plan view of the
leg-circumference extension sections 60.
[0134] For example, as illustrated on the left side of FIG. 9B, the
first lateral welded regions 63 and the second lateral welded
regions 64 may be formed such that their inclination directions
thereof are the same with respect to the fold position f2 and their
positions deviate from each other in the vertical direction. In
such a case, as illustrated on the right side of FIG. 9B, the first
lateral welded regions 63 and the second lateral welded regions 64
that are inclined in directions reverse to each other are arranged
alternately in the vertical direction in plan view of the
leg-circumference extension sections 60.
[0135] For example, as illustrated on the left side of FIG. 9C, the
first lateral welded regions 63 and the second lateral welded
regions 64 may be formed such that their inclination directions are
the same with respect to the fold position f2 and their positions
are the same in the vertical direction. In such a case, as
illustrated on the right side of FIG. 9C, the first lateral welded
regions 63 and the second lateral welded regions 64 that are
inclined in directions reverse to each other are arranged so as to
intersect each other in plan view of the leg-circumference
extension sections 60.
[0136] As illustrated in FIG. 9A and FIG. 9B, the first lateral
welded regions 63 and the second lateral welded regions 64 may
completely deviate from each other, or alternatively, as
illustrated in FIG. 9C, a portion of each first lateral welded
region 63 and a portion of each second lateral welded region 64 may
be superimposed on each other, while the remaining portions thereof
may deviate from each other. Accordingly, since the first lateral
welded regions 63 and the second lateral welded regions 64 deviate
from each other in plan view in the thickness direction, the
lateral welded regions 62 are present in a wider range of a flat
plane in the leg opening forming portions 60a and the overlap
portions 60b, thereby enhancing lateral stiffness of the leg
opening forming portions 60a and the overlap portions 60b. Thus,
the overlap portions 60b are less likely to be affected by lateral
contraction of the waist-circumference sections 20, 30, so that the
leg opening forming portions 60a are likely to be maintained in the
wide-width state, thereby suppressing leakage from around the
legs.
[0137] As illustrated in FIG. 9A and FIG. 9B, in a case in which
the first lateral welded regions 63 and the second lateral welded
regions 64 completely deviate from each other, the lateral welded
regions 62 are formed by sequentially applying pressure with
rotation of an embossing roller, for example, when welding is
performed. This results in stable welding. Further, although not
illustrated, some of the plurality of first lateral welded regions
63 may be superimposed on the second lateral welded regions 64, and
the remaining first lateral welded regions 63 may not be
superimposed on the second lateral welded regions 64. Further, the
size and the shape in plan view of the first lateral welded regions
63 may also be different from those of the second lateral welded
regions 64, and the size and the shape in plan view maybe different
among the first lateral welded regions 63 and/or among the second
lateral welded regions 64. Further, the first lateral welded
regions 63 and the second lateral welded regions 64 may also be
different in arrangement between in the overlap portions 60b and in
the leg opening forming portions 60a. Further, the number of the
first lateral welded regions 63 may be different from the number of
the second lateral welded regions 64. For example, the number of
the second lateral welded regions 64 on the non-skin side is made
greater than the number of the first lateral welded regions 63 on
the skin side, thereby being able to enhance the comfort to the
skin while enhancing the lateral stiffness of the leg-circumference
extension sections 60.
Method of Manufacturing Absorbent Main Body 10
[0138] A description will now be given of a specific method for
manufacturing the absorbent main body 10 including the pair of leak
prevention wall sections 50 and the pair of leg-circumference
extension sections 60. FIG. 10 is a diagram illustrating a flow of
manufacturing the absorbent main body 10. The diaper 1 according to
an embodiment of the present disclosure is continuously
manufactured on a manufacturing line by executing the processes of
S101 to S105 illustrated in FIG. 10.
[0139] In an embodiment of the present disclosure, the processes of
S101 to S105 are executed while a base sheet of the absorbent main
body 10 is being transported at a predetermined transport speed
along a predetermined transport direction. The "base sheet of the
absorbent main body 10" means an exterior continuous sheet 141
configured such that a plurality of the exterior sheets 14
continues in the longitudinal direction (vertical direction) in
FIG. 2, and a direction in which this exterior continuous sheet 141
is transported along the longitudinal direction results in a
transport direction. In the following description, a direction
along the transport direction (i.e., the longitudinal direction of
the exterior sheet 14) is referred to as the MD direction
(corresponding to the vertical direction), and a direction
orthogonal to the MD direction is referred to as the CD direction
(corresponding to the lateral direction).
(S101)
[0140] First, an LSG elastic member placing process is performed to
place the LSG elastic members 51 of the leak prevention wall
sections 50 described above onto the base sheet (the exterior sheet
14) that is transported along the MD direction (S101). FIG. 11 is a
plan view and a cross-section to explain the LSG elastic member
placing process. The exterior sheet 14 in an unfolded state is
illustrated in FIG. 11. In order to simplify the description, FIG.
11 illustrates a state of the above-described exterior sheets 14
obtained by cutting the exterior continuous sheet 141 into product
(diaper 1) units. The same applies to FIG. 12 to FIG. 16 as will be
described below.
[0141] As illustrated in FIG. 11, in the LSG elastic member placing
process (S101), the LSG elastic members 51 in a state of being
stretched in the MD direction (vertical direction) are placed along
the MD direction at the predetermined positions f1 (the
above-described fold positions f1) on both sides in the CD
direction (lateral direction) of the exterior sheet 14 (the
exterior continuous sheet 141). An adhesive such as a hot melt
adhesive (HMA) or the like is applied onto the surface of the LSG
elastic members 51, and the LSG elastic members 51 are joined to
the exterior sheet 14 with the adhesive. Accordingly,
stretchability in the vertical direction (longitudinal direction)
is exhibited at the portions where the LSG elastic members 51 are
joined at the predetermined positions f1 in the exterior sheet 14.
This can raise the leak prevention wall sections 50 to the wearer's
skin side when the diaper 1 has been formed into a pants shape.
[0142] Further, in S101, LSG adhesion portions 55 are also formed,
by providing (applying) the adhesive (for example, the hot melt
adhesive HMA) along the MD direction as illustrated in FIG. 11 in
respective regions inside in the CD direction (lateral direction)
of the predetermined positions f1. The LSG adhesion portions 55 are
adhesion portions for joining portions of the folded exterior sheet
14 together in the thickness direction when the exterior sheet 14
is folded back on itself at the predetermined positions f1, in the
next process (S102). The LSG adhesion portions 55 may be formed
prior to placing the LSG elastic members 51.
(S102)
[0143] Next, a welded region forming process (S102) is performed
such that the two end portions in the CD direction (lateral
direction) of the exterior sheet 14 (the exterior continuous sheet
141) in the unfolded state are folded back on themselves from the
outside toward the inside, and the lateral welded regions 62 and
the vertical welded regions 66 are formed at portions where the
exterior sheet 14 is superimposed by being folded on itself in the
thickness direction. FIG. 12 is a plan view and a cross-section to
explain the welded region forming process. FIG. 13 is an enlarged
view of a region A in FIG. 12 and is a diagram for explaining the
lateral welded regions 62 and the vertical welded regions 66.
[0144] In the welded region forming process (S102), first, the two
end portions of the exterior sheet 14 are folded back on themselves
from the outside toward the inside in the CD direction (lateral
direction) at the predetermined positions f1 where the LSG elastic
members 51 (the LSG elastic members) are placed which serve as
folding positions. That is, the exterior sheet 14 is folded over on
itself in the thickness direction, at the positions f1 where the
LSG elastic members 51 are provided, which serve as bases for
folding back, so as to sandwich the LSG elastic members 51, and is
joined with the LSG adhesion portions 55. Such joined portions are
portions configured to be raised as the leak prevention wall
sections 50 when the diaper 1 is worn. The strength of the leak
prevention wall sections 50 is ensured with the portions of the
folded and superimposed exterior sheet 14 being joined together, so
that the leak prevention wall sections 50 are likely to be
suppressed from falling over or collapsing in shape. Note that,
when the exterior sheet 14 is folded back, used is a fold-back
mechanism (sealer) which is configured to fold back the exterior
continuous sheet 141 in the CD direction while being transported
along the MD direction. In an embodiment of the present disclosure,
the adhesive is not likely to adhere to the sealer since the LSG
adhesion portions 55 are formed inside in the CD direction (lateral
direction) of the predetermined positions f1. This reduces the need
to stop the manufacturing line in order to clean the sealer or
perform maintenance or the like, thereby being able to efficiently
manufacture the diapers 1.
[0145] Then, the lateral welded regions 62 and the vertical welded
regions 66 are formed by partially welding regions located inside
in the lateral direction of the regions that have been joined using
the LSG adhesion portions 55 in the portions where the exterior
sheet 14 has been folded and superimposed on itself. The portions
where the welded regions 62, 66 are formed correspond to portions
that extend in the lateral direction around the leg-circumference
of the wearer, serving as the leg-circumference extension sections
60 when the diaper 1 is worn. By forming the welded regions 62, 66
to have predetermined lateral and vertical lengths, it is possible
to enhance the lateral and vertical stiffness of the
leg-circumference extension sections 60 that are formed using the
exterior sheet 14.
[0146] As illustrated in FIG. 13, in an embodiment of the present
disclosure, the welded regions 62, 66 are formed in the exterior
sheet 14 folded into a double layer in the thickness direction,
such that the plurality of first lateral welded regions 63 are
formed to be arranged in rows at intervals in the longitudinal
direction in each portion on the laterally outer side, and the
plurality of second lateral welded regions 64 are formed to be
arranged in rows at intervals in the longitudinal direction in each
portion on the laterally inner side relative to the first lateral
welded regions 63 across the predetermined position f2 (the
above-described fold position f2). That is, the first lateral
welded regions 63 and the second lateral welded regions 64 are
discontinuous to each other in the lateral direction, and the first
lateral welded regions 63 and the second lateral welded regions 64
are formed so as not to overlap with the predetermined position f2
in the lateral direction. This can suppress increase in the
stiffness of the predetermined positions f2, thereby being able to
tightly folding back when the exterior sheet 14 is folded back on
itself at each predetermined position f2 in an extension section
forming process (S105) which will be described later.
[0147] Further, the first vertical welded regions 67 are formed
outside in the lateral direction of the first lateral welded
regions 63, and the second vertical welded regions 68 are formed
inside in the lateral direction of the second lateral welded
regions 64. Note that the lateral welded regions 62 and the
vertical welded regions 66 are formed so as not to overlap with
ends 14e constituting edges of the exterior sheet 14 in the lateral
direction (see FIG. 12). This suppresses these edge portions (14e)
from increasing in stiffness and the sheet member from becoming
hard, thereby preventing degradation in texture even in cases where
the edge portions are pressed against the skin of the wearer when
the diaper 1 is worn.
[0148] The lateral welded regions 62 (63, 64) are formed such that
multiple of the dot-shaped weld portions 69 are formed to be
arranged in the lateral direction. Specifically, pairs of rows each
having three dots of the weld portions 69 arranged to be inclined
with respect to the lateral direction are arranged in rows in the
vertical direction without being aligned with one another in the
lateral direction. Similarly, the vertical welded regions 66 (67,
68) are also formed such that pairs of rows each having multiple of
the dot-shaped weld portions 69 along the vertical direction are
arranged in the lateral direction without being aligned with one
another in the vertical direction. Each of the weld portions 69 is
formed, for example, by a welding means such as ultrasonic welding
or the like by employing an embossing roller having its rotational
axis set along the CD direction and using a single projection in a
projection pattern provided on the outer circumferential face of
the embossing roller. However, the weld portions 69 may also be
formed using another welding means, such as heat welding, laser
illumination, or the like.
[0149] Accordingly, such welded regions 62, 66 may be obtained by
being partially welded using the dot-shaped weld portions 69,
thereby being able to reduce the area of each weld portion 69. This
makes it possible to concentrate and repeatedly apply ultrasonic
vibrations or the like onto individual points using a projection
pattern during welding, thereby being able to perform stable
welding. However, the shapes of the welded regions 62, 66 are not
limited thereto and, for example, the planar shape of a single
protrusion provided on the outer circumferential face of an
embossing roller may be formed into the same shape as the welded
regions 62, 66, such that the entire welded regions 62, 66 are
welded. That is, the welded regions 62, 66 may be formed in linear
shapes in which the entire regions surrounded by dashed lines in
FIG. 13 are welded.
[0150] Moreover, the predetermined length in the lateral direction
of the lateral welded regions 62 indicates a length in the lateral
direction from one end to the other end in the lateral direction of
the lateral welded regions 62, and is indicated by L62 in FIG. 13.
As long as the shape of the lateral welded regions 62 has a
predetermined length (L62) in the lateral direction (CD direction),
the shape of the lateral welded regions 62 may be a shape extending
parallel to the lateral direction (not illustrated), and may also
be a shape inclined with respect to the lateral direction as in an
embodiment of the present disclosure.
[0151] However, in a case where the projection pattern of the
embossing roller is arrayed parallel to the CD direction and the
lateral welded regions 62 are formed parallel to the CD direction,
the lateral welded regions 62 along the CD direction (lateral
direction) is formed at the same instant and timing at which a row
in the projection pattern contacts the exterior sheet 14 (the
exterior continuous sheet 141) along with the rotation of the
embossing roller. In such cases, it is difficult to apply uniform
pressure over the entire regions in the lateral direction, and thus
the welding strength might be uneven in the lateral direction of
the lateral welded regions 62. Further, the projection pattern is
likely to be worn out due to a large pressure being applied all at
once to a row of the projection pattern. In contrast thereto, when
the lateral welded regions 62 are inclined with respect to the
lateral direction (CD direction), the lateral welded regions 62 are
formed while the point to which pressure is applied is being
sequentially shifted along with the rotation of the embossing
roller, so that local welding defects or the like are less likely
to occur and the welding strength is less likely to be uneven.
Moreover, since the place to which pressure is applied is
sequentially shifted, the projections provided on the outer
circumferential face of the embossing roller are less likely to be
worn out, thereby being able to efficiently perform
manufacturing.
[0152] The predetermined lateral length of the lateral welded
regions 62 maybe of any length as long as it is greater than 0 mm,
however the welded regions 62 are preferably elongated to some
extent. For example, in cases in which the lateral width of the
leg-circumference extension sections 60 is 40 mm, the length in the
lateral direction of the lateral welded regions 62 is preferably in
a range of from 7.5 mm to 27.5 mm, and is more preferably about
17.5 mm.
(S103)
[0153] An elastic member placing process (S103) is then performed
in which the leg-circumference elastic members 61 are placed in a
predetermined region of the exterior sheet 14 (the exterior
continuous sheet 141). FIG. 14 is a plan view and a cross-section
to explain the elastic member placing process.
[0154] First, an adhesive for forming the end joined portions 52
and the side joined portion 53 of the leak prevention wall sections
50 is applied to in the portions in the lateral direction (CD
direction) outside of the lateral welded regions 62 and the
vertical welded regions 66 on the skin side face of the
double-layered exterior sheet 14. In an embodiment of the present
disclosure, as illustrated in FIG. 14, the side joined portions 53
are formed further outside in the lateral direction of the first
vertical welded region 67 that is formed outermost in the lateral
direction. That is, the side joined portions 53 are formed so as
not to overlap with at least the welded regions 62, 63 in the
lateral direction. Adhesive for forming the back sheet joined
portion 44 to join the back sheet 13 in the next process (S104) may
also be applied to a central region in the lateral direction (CD
direction) on the skin side face of the exterior sheet 14 in this
process (see FIG. 14). The order in which the joined portions 44,
52, 53 are formed may be freely selected. However, these joined
portions are formed in positions on the skin side face of the
exterior sheet 14 that do not interfere with each other, and thus
the adhesive can be applied thereto at the same time. Application
of the adhesive at the same time can reduce the manufacturing cost
while making the facility space of the manufacturing line more
compact.
[0155] After the joined portions 44, 52, 53 are formed, the
plurality of leg-circumference elastic members 61 in a stretched
state along the vertical direction (MD direction) are joined to
portions inside in the lateral direction (CD direction) of the side
joined portions 53 on the skin side face of the exterior sheet 14.
Note that the leg-circumference elastic members 61 is applied with
the adhesive in advance in the range of a region L61 illustrated in
FIG. 14, thereby providing stretchability in the vertical direction
(MD direction) to the exterior sheet 14 in the range of this region
L61. Accordingly, stretchability in the vertical direction is
exhibited at least in the range of the region L61 in the
leg-circumference extension sections 60, thereby improving the fit
of the leg-circumference extension sections 60 around the legs of
the wearer when the diaper 1 is worn.
[0156] In an embodiment of the present disclosure, four
leg-circumference elastic members 61a to 61d from the inside to the
outside in the lateral direction are provided. From thereamong, the
leg-circumference elastic members 61b and 61c are placed so as to
overlap with the lateral welded regions 64 (62) in the lateral
direction. The leg-circumference elastic member 61a located
innermost in the lateral direction is placed at a position between
the absorbent body 12 and the lateral welded regions 62 in the
lateral direction. The leg-circumference elastic member 61d located
outermost in the lateral direction is placed at the predetermined
position f2 in the lateral direction. The predetermined position f2
is the position corresponding to the laterally outer end 60d of
each of the leg-circumference extension sections 60 when the diaper
1 has been formed into a pants shape.
[0157] In the manufacturing method according to an embodiment of
the present disclosure, the leg-circumference elastic members 61
are placed in S103 after the lateral welded regions 62 are formed
at S102, thereby being able to cause a stretching force in the
vertical direction by virtue of the leg-circumference elastic
members 61 to act on the regions where the lateral welded regions
62 (64) are formed in the leg-circumference extension sections 60.
If the lateral welded regions 62 are formed after placing the
leg-circumference elastic members 61, the leg-circumference elastic
members 61 might be cut by the pressure from the embossing roller
or the like that is applied when the lateral welded regions 62 are
formed, such that a stretching force might no longer be exhibited
in the leg-circumference extension sections 60. In contrast
thereto, according to the manufacturing method of an embodiment of
the present disclosure, it is possible to form the lateral welded
regions 62 in regions overlapping with the leg-circumference
elastic members 61 without impairing the stretching force of the
leg-circumference elastic members 61. The effect of placing the
leg-circumference elastic members 61 and the lateral welded regions
62 so as to overlap with each other in the leg-circumference
extension sections 60 will be described later.
(S104)
[0158] Next, an absorbent body transferring process (S104) is
performed in which the absorbent body 12 (the absorbent body 12
wrapped in the top sheet 11) is attached to the skin side of the
exterior sheet 14 (the exterior continuous sheet 141). FIG. 15 is a
plan view and a cross-section to explain the absorbent body
transferring process.
[0159] First, the back sheet 13 is joined to the skin side face of
the exterior sheet 14. The back sheet 13 is placed so as to overlap
with the leg-circumference elastic members 61a to 61c in the
lateral direction (CD direction). That is, the back sheet 13 is
placed so as to cover at least a region between the
leg-circumference elastic member 61c placed on one side in the
lateral direction and the leg-circumference elastic member 61c
placed on the other side in the lateral direction, from the skin
side in the thickness direction, and the back sheet 13 is joined to
the skin side face of the exterior sheet 14 with the back sheet
joined portion 44 and the adhesive applied to the surface of the
leg-circumference elastic members 61.
[0160] Note that the back sheet 13 can also be placed further on
the non-skin side with respect to the leg-circumference elastic
members 61 in view of the configuration of the absorbent main body
10. However, in such cases, a portion of the leg-circumference
elastic members 61 might be exposed to the skin side, and thus the
adhesive applied onto the surface of the leg-circumference elastic
members 61 might adhere to the wearer's body or the like when the
diaper 1 is worn, which might cause discomfort to the wearer. In
contrast thereto, in the diaper 1 according to an embodiment of the
present disclosure, the back sheet 13 is placed so as to cover the
skin side of the leg-circumference elastic members 61a to 61c in
S104, thereby suppressing the leg-circumference elastic members 61
from being exposed to the skin side, so that the adhesive is less
likely to adhere to the wearer's body while the diaper 1 is
worn.
[0161] Then, the absorbent body 12 is joined (transferred) to the
skin side face of the back sheet 13 through the absorbent body
joined portion 43 that is formed with the adhesive applied to the
skin side face of the back sheet 13.
(S105)
[0162] Next, a leg-circumference extension section forming process
(S105) is performed in which the leg-circumference extension
sections 60 are formed by folding the two lateral end portions of
the exterior sheet 14 (the exterior continuous sheet 141) back on
themselves once again from the outside to the inside. FIG. 16 is a
plan view and a cross-section to explain the leg-circumference
extension section forming process. The cross-section in FIG. 16
corresponds to FIG. 3.
[0163] In the extension section forming process (S105), the two end
portions of the exterior sheet 14 are folded back on themselves
from the outside toward the inside in the lateral direction at the
predetermined positions f2 at which the leg-circumference elastic
members 61d are placed which serve as the fold positions. Then, the
opposing faces of the exterior sheet 14 folded in the thickness
direction are joined together using the end joined portions 52 and
the side joined portions 53. Accordingly, the leg-circumference
extension sections 60 are formed to extend outward in the lateral
direction. As described above, since no lateral welded regions 62
or vertical welded regions 66 are formed at the predetermined
positions f2, the stiffness of the exterior sheet 14 does not
become too high at the predetermined positions f2, thereby being
able to tightly fold the exterior sheet 14. Thus, it is possible to
form the leg-circumference extension sections 60 into neat planar
shapes.
[0164] Then, the exterior sheet 14 is folded back on itself at the
predetermined positions f2 such that the first lateral welded
regions 63 and the first vertical welded regions 67 are
superimposed in the thickness direction onto the second lateral
welded regions 64 and the second vertical welded regions 68,
thereby bringing about a state in which the leg-circumference
elastic members 61b and 61c are sandwiched therebetween. That is,
the leg-circumference extension sections 60 are formed such that at
least a portion of the plurality of leg-circumference elastic
members 61 overlaps with the lateral welded regions 62.
[0165] In such a diaper in which leg-circumference extension
sections extend in the lateral direction to a large extent as in
the diaper 1 (see FIG. 1), there has been a tendency to degrade the
fit since the leg-circumference extension sections contract and/or
curl in the lateral direction while the diaper is worn. In contrast
thereto, in the diaper 1 manufactured by the manufacturing method
according to an embodiment of the present disclosure, the lateral
stiffness of the leg-circumference extension sections 60 is
increased by providing the plurality of the lateral welded regions
62. This can make it easier to maintain the leg-circumference
extension sections 60 in a planar shape. That is, even in a state
in which a contraction force caused by the leg-circumference
elastic members 61 is acting, it is possible to suppress
contraction and curling of the leg-circumference extension sections
60 in the lateral direction, so that the leg-circumference
extension sections 60 is likely to be maintained in a state of
having some lateral width (wide-width state). Moreover, with a
contraction force in the vertical direction acting while the
leg-circumference extension sections 60 being maintained in the
planar shape, many creases running along the lateral direction are
formed in the surface of the leg-circumference extension sections
60. Such undulations of the creases can make it possible to achieve
pleasant feel to the touch in the leg-circumference extension
sections 60. This can make it possible to closely fit around the
wearer's legs through contact of faces having wide widths thereby
suppressing leakage of excrement from around the legs, while
improving the fit of the leg-circumference extension sections 60
when the diaper 1 is worn.
[0166] Note that, as illustrated in the cross-section of FIG. 16,
the diaper 1 has such a configuration that the exterior sheet 14 is
folded back at the predetermined positions f2 and superimposed on
itself in the thickness direction, and the back sheet 13 is
interposed in the thickness direction between the leg-circumference
elastic members 61a to 61c, and the end joined portions 52 and the
side joined portions 53 in such a superimposed state. That is, in
the absorbent main body 10, the leg-circumference elastic members
61a to 61c do not contact the end joined portions 52 and the side
joined portions 53 in the thickness direction. If they are placed
such that the end joined portions 52 and the side joined portions
53 are superimposed on the leg-circumference elastic members 61 in
the thickness direction, the stretching force caused by the
leg-circumference elastic members 61 acts also on portions other
than a region L61 where the adhesive is applied to its surface in
the leg-circumference elastic members 61. The two end portions in
the vertical direction of the absorbent main body 10, and
furthermore the front waist-circumference section 20 and the back
waist-circumference section 30 might contract in the vertical
direction. In contrast thereto, in an embodiment of the present
disclosure, since the back sheet 13 is placed on the skin side of
the leg-circumference elastic members 61, the end joined portions
52 and the side joined portions 53 are suppressed from contacting
the leg-circumference elastic members 61, thereby suppressing the
contraction force caused by the leg-circumference elastic members
61 from acting onto the front waist-circumference section 20, the
back waist-circumference section 30, and the like.
[0167] In a state in which each of the leg-circumference extension
sections 60 have been formed, the leg-circumference elastic member
61a located at the position innermost in the lateral direction
among four leg-circumference elastic members 61a to 61d is placed
at the position between the absorbent body 12 and the welded
regions 62, 66 in the lateral direction. Thus, by virtue of the
contraction of the leg-circumference elastic member 61a, a portion
outside in the lateral direction of the leg-circumference elastic
member 61a in the leg-circumference extension section 60 serves as
the base for being raised to the skin side of the wearer when the
diaper 1 is worn, and the upright height of the leg-circumference
extension section 60 is ensured. Accordingly, the leg-circumference
extension sections 60 are likely to closely fit around the legs of
the wearer.
[0168] On the other hand, the leg-circumference elastic member 61d
located at the position outermost in the lateral direction among
four leg-circumference elastic members 61a to 61d is placed at the
position corresponding to the laterally outer end 60d of the
leg-circumference extension section 60. Accordingly, the
leg-circumference extension sections 60 can be made in securely
close contact with the wearer up to the position corresponding to
the laterally outer ends 60d by virtue of the contraction of the
leg-circumference elastic members 61d. In particular, since the
lateral welded regions 62 do not reach the laterally outer ends 60d
of the leg-circumference extension sections 60 in the diaper 1, the
leg-circumference extension sections 60 might be less likely to be
maintained in a planar shape in the region corresponding to the
outside ends 60d. However, the leg-circumference extension sections
60 closely fit around the legs of the wearer using the contraction
force of the leg-circumference elastic members 61d, thereby being
able to suppress degradation in fit of the leg-circumference
extension sections 60.
[0169] Further, when the leg-circumference extension sections 60
are formed in the extension section forming process (S105), the
exterior sheet between the end joined portions 52 in a pair in the
vertical direction is raised to the skin side of the wearer based
on the side joined portions 53 by virtue of the contraction of the
LSG elastic members 51, thereby forming the leak prevention wall
sections 50. The side joined portions 53 (i.e., the bases for
raising the leak prevention wall sections 50) are formed so as not
to overlap with the welded regions 62, 66 in the lateral direction
(S103), and thus the stiffness in the regions where the side joined
portions 53 are formed in the exterior sheet 14 is not increased.
Accordingly, the exterior sheet 14 is likely to be naturally bent
about the bases of the side joined portions 53, so that the leak
prevention wall sections 50 are easily raised.
[0170] In the diaper 1, the leak prevention wall sections 50 and
the leg-circumference extension sections 60 can be integrally
formed by folding the exterior sheet 14 back on itself. That is, in
the diaper 1, there is no seam in sheet member among the absorbent
main body 10, the leak prevention wall sections 50, and the
leg-circumference extension sections 60. This makes it possible to
suppress leakage of excrement from seams in sheets around the legs
of the wearer.
[0171] The above embodiments of the present disclosure are simply
to facilitate understanding of the present disclosure and are not
in any way to be construed as limiting the present disclosure. The
present disclosure may variously be changed or altered without
departing from its gist and encompass equivalents thereof.
[0172] For example, such a diaper (so-called two piece type of
diaper) may be employed that is integrated such that an exterior
sheet 14 connects a front waist-circumference section 20 and a back
waist-circumference section 30 together. Moreover, the absorbent
article according to the present disclosure is not limited to a
pull-on disposable diaper, but may be a tape-type disposable
diaper. In a case of such a tape-type disposable diaper or the
like, an elastic member that is stretchable in the lateral
direction may be provided to at least one of waist-circumference
sections in a pair. Other applications include pull-on sanitary
napkins and urine absorbing pads.
REFERENCE SIGNS LIST
[0173] 1: diaper (absorbent article, pull-on absorbent article);
[0174] 10: absorbent main body; 11: top sheet; [0175] 12: absorbent
body; 121: absorbent core; 122: core-wrapping sheet; [0176] 13:
back sheet (liquid impermeable sheet); 14: exterior sheet
(continuous sheet); [0177] 141: exterior continuous sheet; [0178]
20: front waist-circumference section (waist-circumference
section); 21 sheet; 21 sheet [0179] 22: waist-circumference elastic
member (elastic member stretchable in a lateral direction); [0180]
30: back waist-circumference section (waist-circumference section);
31 sheet; 31 sheet; waist-circumference elastic member (elastic
member stretchable in a lateral direction); [0181] 40: adhesive
region; 41: non-joined region; 42 to 44: joined region; [0182] 50:
leak prevention wall section; 51: elastic member (LSG elastic
member); [0183] 52: end joined portion; 53: side joined portion;
55: LSG adhesion portions; [0184] 60: leg-circumference extension
sections (extension section); [0185] 60a: leg opening forming
portion (portion where an extension section forms a leg opening);
60b: overlap portion; [0186] 61: leg-circumference elastic members
(elastic member stretchable in a vertical direction); [0187] 62:
lateral welded regions (welded region); [0188] 63: first lateral
welded region (first welded region) [0189] 64: second lateral
welded regions (second welded region) [0190] 66: vertical welded
region; 67: first vertical welded region; [0191] 68: second
vertical welded region; 69: weld portion; [0192] LH: leg opening;
and BH: waist opening.
* * * * *